Round 21: 4 Things You Need to Know

The 5 things you need to know about the round 21 clash between the Canterbury-Bankstown Bulldogs and the Sydney Roosters at Allianz Stadium.

#1: PAST 8 CLASHES

The Bulldogs have not enjoyed as much success as they would have liked over the past eight encounters against the Roosters.

The Roosters have won five of the last eight matches, including four of the last five.

The Bulldogs only win in the last five outings was in round five from the 2014 season when a Josh Reynolds field goal was the difference to give the Bulldogs a 9-8 victory.

These two sides have met this year with the Roosters running away with a 24-10 win in round 10 at ANZ Stadium.

2015: Roosters 24 Bulldogs 10

2014: Roosters 32 Bulldogs 12, Bulldogs 9 Roosters 8

2013: Roosters 20 Bulldogs 18, Roosters 38 Bulldogs 0

2012: Bulldogs 42 Roosters 10, Bulldogs 30 Roosters 12

2011: Roosters 32 Bulldogs 28

#2: ROOSTERS ROCK SOLID

The Roosters defence has been a standout all season and the cornerstone to many of their victories in 2015.

They are ranked number one for points against with 212 (averaging 11.7 points per game), ranked number one for tries conceded with 37 and in their last five matches have only conceded 36 points (averaging 7.2 points per game), which included a 24-0 win over the Warriors.

While the Bulldogs have conceded 354 points this year (averaging 19.6 ppoints per game), conceded 62 tries in 2015 to date and in their last five games have conceded 54 points (averaging 10.8 points per game).

The Roosters have based their game on defence under the watchful eye of Trent Robinson over the past few seasons, but if there is a concern, it's the fact that James Maloney is ranked number one in the NRL in 2015 for missed tackles with 81.

Aside from this, the Roosters defesive line is tough to crack.

#3: ROOSTERS HAVE THE FUMBLES

The Roosters may have the number one defence in the game, but they are ranked 16th in the NRL for handling errors made.

The Roosters have made a total of 188 handling errors, the most by an team in 2015 (averaging 10.4 per game), compared to the Melbourne Storm who are ranked number one with a total of 123 handling errors (averaging 6.8 per game).

The Bulldogs have made a total of 152 handling errors in 2015.

Two of the Roosters main contributors are James Maloney and Michael Jennings - both have made 13 handling errors in 2015 and are ranked 4th and 5th for handling erros made by a player.

Anthony Milford is number one with 15.

The Roosters handling errors also has an effect on their completion rate with an average of 72% per game, ranking them 15th overall for completion rates, while we are ranked 11th with an average of 74%.

#4: BACK 5 VULNERABLE

The Roosters back five have been exceptional in 2015 when it comes to their attacking stats.

The Roosters back five are number one in the NRL for total metres, number one in the NRL for kick return metres, number one in the NRL for tackle breaks, second in the NRL for line breaks, fourth in the NRL for tries scored and are the second best team in the NRL for kick defusal, but their back five are the worst in the NRL for errrors.

The Roosters back five have made a total of 104 errors, compared to the Brisbane Broncos who have made 56, while the Bulldogs back five have made a total of 65 errors.

CLUB BACK 5 ERRORS: