With the 2021 NRL season almost upon us and a look at where teams will score their tries already in the books, it's time to check the other side of the ball. The side that doesn't make the highlight reels so often but determines the premiership winner more often than not.

The trend of Top 3 defences winning the premiership (outside of the 2015 Cowboys) continued in 2020. Conceding just 14.3 points per game, the Melbourne Storm finished their premiership-winning season second in defence, behind the Panthers at 13.4 points per game.

Melbourne and Penrith look set to continue in their defensive ways in 2021. However, the Brisbane Broncos, North Queensland Cowboys, Manly-Warringah Sea Eagles, Wests Tigers and Canterbury-Bankstown Bulldogs need to make significant improvements if they're to threaten the Top 8 this season.

Brisbane Broncos

2020 Tries conceded locations: Left - 39% , Middle - 24% , Right - 36% 

The try location data doesn't tell the story of the 2020 Brisbane Broncos. It didn't matter where on the field the opposition targeted, they were a good chance at scoring. Brisbane's 31.2 points conceded per game was the worst mark in the NRL by over five points. They conceded almost an extra try to the team ranked 15th.

Nobody likes to call footy players soft. That's all that can be said for the Broncos, though. No good teams concede too many tries in the middle of the field, and Anthony Seibold's side allowed more than any other team (26).

A change in coach should help the Broncos in 2021; Seibold lost the dressing room early into 2020, and it showed in their defensive efforts. Some injury luck and the cohesion that comes with defending beside the same bloke for consecutive weeks will help too. However, they will need to shave 10 points off their 2020 number if they're to push for the Top 8. 

Canberra Raiders

2020 Tries conceded locations: Left - 42% , Middle - 18% , Right - 40% 

The Canberra Raiders kicked their inconsistency issues of 2018 away by improving their defence in 2019. That continued through to 2020, with the Raiders conceding the fourth-fewest points at 16.7 per game. 

Ricky Stuart ensured Canberra didn't have a major weakness in their defensive line for the opposition to target. That is most evident by their even splits across the field with 27 tries allowed through the left edge and 26 through the right edge.

We've harped on about cohesion in defence plenty here. Thanks to injury issues forcing role players onto the field more often than they would have liked in 2020, the Raiders are well-positioned to be a cohesive and strong defensive unit moving forward.

Canterbury-Bankstown Bulldogs

2020 Tries conceded locations: Left - 47%, Middle - 15%, Right - 38% 

No avenue proved more fruitful for attacking teams than the Canterbury-Bankstown Bulldogs left edge. The 43 tries conceded down that side is the most by one team in any area of the field.

A rotation of players moving in and out of the starting 13 on the left edge was the main cause for the thoroughfare. Kieran Foran couldn't stay on the field while the Bulldogs coaching staff couldn't land on a long-term, consistent centre.

Things are looking up for the Dogs overall. Trent Barrett has made some encouraging signings leading most to anticipate an improvement in attack. It will all be for nothing if they can't close up their left edge defence, though.

Cronulla-Sutherland Sharks

2020 Tries conceded locations: Left - 42%, Middle - 27%, Right - 31% 

The Cronulla-Sutherland Sharks' 27% of tries conceded through the middle ended up alongside the Dragons as the highest proportion in the NRL. The 24 total tries conceded in the middle finished as the second-most behind an awful Broncos defence. A lot came down to lazy efforts and older forwards struggling with mobility. 

It's an area John Morris eventually addressed, but he needs to continue fine-tuning the Sharks defence if they're to improve on the 24.4 points conceded per game last season. No other Top 8 team conceded more than 20 points per game.

Gold Coast Titans

2020 Tries conceded locations: Left - 33%, Middle - 24%, Right - 43% 

The Gold Coast Titans are buzzing heading into the 2021 NRL season. They've won five games in a row and have added David Fifita and Tino Fa'asuamaleaui to the side. Expectations are that this team makes a return to finals footy.

While it's safe to assume the Titans improve with the ball in their hands, their 23.2 points conceded per game in 2020 also needs to improve to a Top 8 level. Fifita's edge is one to watch early as he builds his combinations with players on either side of him. So too is Mitch Rein, who, while a strong attacking player, isn't known for his stringent defence.

The Titans are an exciting young side. As already mentioned, they are sure to improve on their 17.3 points per game last season. How they gel defensively will likely be what determines their place inside or outside the Top 8.

Manly-Warringah Sea Eagles

2020 Tries conceded locations: Left - 34%, Middle - 19%, Right - 47% 

No team conceded more tries down the right side of the field than the Manly-Warringah Sea Eagles. It became a consistent source of points for the opposition with 42 tries scored on that side throughout the season.

Like the Bulldogs, injuries made things difficult for the Sea Eagles. Tom Trbojevic's absence at fullback took away a major voice in how the defence numbered up as well.

Manly's injury woes have been the defining factor of their last two seasons. Until they can start to put a consistent team out on the field, they'll continue to struggle defensively.

Melbourne Storm

2020 Tries conceded locations: Left - 37%, Middle - 14%, Right - 49% 

The Melbourne Storm conceded 51 tries in 2020. The 49% to come through the right edge is the highest percentage of all 16 teams anywhere on the field. However, rather than show a weakness in their right side (the 25 total tries conceded was the second-fewest in the NRL), it highlights just how strong they were everywhere else. 

No team conceded fewer tries down the left edge (19) or through the middle (7) than the Storm. 

While Melbourne's attack finished at the top of the pile in 2020, their defence is always a staple of their season. It's the leading reason behind their prolonged spell as one of the elite teams in the NRL.

Newcastle Knights

2020 Tries conceded locations: Left - 32%, Middle - 24%, Right - 44% 

The Newcastle Knights can be encouraged by their defensive performance in 2020. Despite long-term injuries to key players and regular changes in the outside backs, the Knights conceded just 20 points per game - 6th in the NRL. 

Conceding 17 tries in the middle is a slight cause for concern. When you look at the top three defensive teams in the competition in the Panthers, Storm and Raiders, none allowed more than ten tries through the middle of the field.

Newcastle are without Kalyn Ponga and Blake Green to start the season. Their attack will suffer as a result. However, the Knights have been awarded a relatively easy draw to start the year. We're going to get a good idea of their defensive capabilities inside the first six rounds.

North Queensland Cowboys

2020 Tries conceded locations: Left - 40%, Middle - 15%, Right - 45% 

Kyle Feldt and Esan Marsters made up the worst defensive duo in the NRL after Round 10 in 2020. The pair had contributed 27 try causes between them. Marsters only played two more games all season, and on the other side of the field. Still, Feldt finished the year with an NRL-high 28 try causes in his 20 games.

North Queensland's 26 points conceded per game all but ended their hopes of cracking the Top 8. Now, Todd Payten is in the coaches box, and while he did incredible things with the Warriors last season, he needs to find a first-choice 17 he can stick with. More than anything, he needs to identify his backline after it was changed 32 times across their last 43 rounds.

A new voice and a consistent 17 can work wonders for the Cowboys on both sides of the ball.

Parramatta Eels

2020 Tries conceded locations: Left - 41%, Middle - 11%, Right - 48% 

The Parramatta Eels played with a premiership contending defence, conceding just 16.5 points per game in 2020. It's their flailing attack throughout the second half of the season that let them down.

Parramatta were far from perfect, though. Waqa Blake's struggles are highlighted by the high proportion of tries coming through the right edge. Blake's teammates made up for it in the middle, though. The Eels ended up alongside the Storm as the best defensive middle in the NRL, conceding seven tries through the centre-third all year.

The defensive principles are there for the Eels to ensure finals footy. Whether or not they can score points all year will determine their premiership credentials come September.

Penrith Panthers

2020 Tries conceded locations: Left - 41%, Middle - 20%, Right - 39% 

The Penrith Panthers left edge attack caught fire and Nathan Cleary put in a Dally M-calibre season, but it's the NRL-best 13.4 points conceded per game that got the Penrith Panthers to Grand Final Day.

In particular, their ability to shut out opponents early while building a lead themselves. David Nofoaluma's try in the 6th minute of Round 16 ended an incredible run. 

Much like Melbourne, Penrith's splits showcase their strength across the park rather than highlight any one weakness. It will be difficult for the Panthers to keep these numbers up, though. Blessed by the injury gods and with State of Origin to deal with this season, the cohesion they played with almost all season won't be there for the full 25 rounds in 2021.

South Sydney Rabbitohs

2020 Tries conceded locations: Left - 39%, Middle - 16%, Right - 45% 

The South Sydney Rabbitohs attack made headlines to finish the 2020 season. However, it's their 18.1 points conceded per game that helps to prop up their premiership credentials in 2021. It's an impressive number given the turnover on the edge and while Latrell Mitchell adjusted to life as a fullback.

Campbell Graham made the move into the centres fulltime and struggled at times. He's a contributor to the 34 tries South Sydney conceded down the right edge. But with a full season of experience in the centres and an experienced winger outside him, expect Graham to look more comfortable in defence moving forward. It's the only genuine concern around South Sydney's defence heading into the season.

St George Illawarra Dragons

2020 Tries conceded locations: Left - 29%, Middle - 27%, Right - 44%

The Good: The St George Illawarra Dragons left edge conceded just 23 tries all season. Only three teams allowed less.

The Bad: Only five teams conceded more than the Red V's 35 tries down the right. Meanwhile, the 21 tries conceded in the middle uncovered a soft underbelly, contributing to the sacking of a head coach once again.

Sydney Roosters

2020 Tries conceded locations: Left - 30%, Middle - 24%, Right - 46% 

Despite conceding 60 points in Round 20 last season, the Sydney Roosters still finished inside the top five in defence, conceding 17 points per game.

It's no surprise that the Roosters started to leak a few points late in the year. Back-to-back premiers and playing with a target on their back for the best part of three years, the Chooks ran out of gas. It showed in their defence more than anything.

Pairing Lachlan Lam with Joseph Manu on a right side that conceded 46% of Sydney's total tries is a slight cause for concern. However, a rested and reinvigorated Roosters side looks set to improve on the defensive side of the ball overall.

New Zealand Warriors

2020 Tries conceded locations: Left - 40%, Middle - 19%, Right - 40% 

Ask people how they thought the New Zealand Warriors would go after Stephen Kearney was sacked after Round 6, and most anticipated a wooden spoon. Finishing last defensively - even behind the Broncos - wouldn't have come as a shock. Remarkably, the Warriors finished in the middle of the pack allowing 22.9 points through them per game.

They showed fight and a level of consistency in defence that hasn't always been there for the Warriors. While they've always got a surprising performance in them, the surprise in 2020 was how well they defended across 20 rounds away from home.

Nathan Brown is dealing with 25 rounds this season. It's going to be a challenge for him to keep the playing group engaged if they aren't able to return home at some point in 2021. 

Wests Tigers

2020 Tries conceded locations: Left - 33%, Middle - 24%, Right - 42% 

Michael Maguire was quick to separate the Leilua brothers after Round 2 last season. They struggled to defend beside each other with Luciano soon moved to the left edge. However, the right side continued to be an issue for Wests. Benji Marshall, in particular, couldn't add enough with the ball in hand to make up for his performances in defence.

Now, Maguire is rolling the dice on the Leilua brothers again. They're expected to line up on the same side of the field in Round 1. The difference now is Luciano is well on his way to being one of the best backrowers in the NRL. If he can build a strong partnership with his brother and limit the number of times Joey loses his head, they will make for one of the most exciting duos all season.

Up against the Raiders and Roosters to start the year, we're going to get a good read on Wests defence early.

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