Three key battles pivotal to Harlequins v Leinster showdown

Given the emphasis Leinster place on kicking to contest and kicking for territory as part of what teams now call their "exit strategies" Harlequins fullback Mike Brown is likely to be a central figure in Sunday's European Champions Cup match at The Stoop.

The England international won the 2014 Six Nations player of the tournament largely on the strength on his ability to counter-attack, invariably running the ball back and beating the first, and on several occasions, a handful of would-be tacklers. Leinster are forewarned.

Conor O’Shea, a former Leinster fullback, will underline the folly of kicking poorly to Rob Kearney, who is in excellent form of late. His prowess in the air is well documented while he was a conspicuous line breaker for Ireland last month. Whichever fullback has the more prominent afternoon in the kick-return stakes will provide their team with an edge.

Joe Marler was not the obvious choice to succeed Chris Robshaw as Harlequins captain but the 24-year-old was given the role at the start of the season. His appearance – multi-coloured Mohican haircut in the past and tattoos – has occasionally overshadowed his talent but when he was away last month with England the Quins scrum suffered hugely. It is something Leinster’s Marco Caputo will have noted.

Marler was a teenager when Mike Ross was at Harlequins so there will be a little familiarity. The Irish man is a key player for Leinster and now just in the scrum but also his work-rate but it is the former area where the Irish province will hope Ross can get the upper hand on his former club-mate.

The breakdown, as is the case in every game, is a crucial contestable, so to speak. Harlequins are at their most fluid and dangerous when scrumhalf Danny Care gets quick, front-foot ball and are less effective in attack when the game is more stop-start. They like a match with a high tempo, that’s fast and loose.

That would have suited Leinster in the past but they’re more content to chase territory and apply pressure rather than look to open up from inside their own half.

Robshaw and Dominic Ryan, assuming Leinster coach Matt O'Connor rewards the latter's superb recent form, share many qualities; neither would be considered an out-and-out groundhog in terms of the openside flanker role but both are strong over the ball, on the ball and as tacklers.

KICK/RETURN

MIKE BROWN

Position: Fullback

Age: 29

Height: 1.83m (6')

Weight: 90kg (14st 2lbs)

Caps: 33 (6 tries)

Why he's so important? Voted the 2014 Six Nations Championship player of the tournament, on foot of his excellent counter-attacking game and solidity under the high ball.

He’s a feisty character. If Leinster kick poorly he’ll make them pay. He’s a very strong runner that invariably breaks the first tackle.

Trivia: Engaged to Eliza, the daughter of Tony Woodcock, not the All Black centurion prop but the former Nottingham Forest, Arsenal and England striker. They, Mike and Eliza, have deferred their wedding until 2016 so as not to interfere with his World Cup preparations.

ROB KEARNEY

Position: Fullback

Age: 28

Height: 1.85m (6'1")

Weight: 90kg (14st 2lbs)

Caps: 57 (10 tries)

Why he's so important? Enjoyed an excellent November series with Ireland and will be hoping to continue that form into two pivotal clashes with his province.

Ability under the high ball is unquestioned as is a facility now to regularly beat the first tackler. Decision making in possession will be important.

Trivia: Aside from his try tally has also kicked a conversion for Ireland; it was against Italy in the 2009 Six Nations Championship at the Stadio Flaminio in Rome.

SCRUM BATTLE

JOE MARLER

Position: Loosehead prop

Age: 24

Height: 1.83m (6')

Weight: 114kg (17st 13lbs)

Caps: 26

Why he's so important? Has taken over as club captain from Chris Robshaw to allow the latter to concentrate on his England duties.

Forget about the style peccadilloes of the past, the coloured Mohican haircut, the extensive tattoos; he contributes handsomely in both the tight and around the pitch. The Quins scrum is considerably weaker without him.

Trivia: Said at the time that beating Ireland in 2013 was his best achievement while wearing an England jersey. The English team won 12-6 at the Aviva stadium.

MIKE ROSS

Position: Tighthead prop

Age: 34

Height: 1.88m (6'2")

Weight: 124kg (19st 7lbs)

Caps: 44

Why he's so important? Anchors the scrum for club and province and his influence can be gleaned in the difference when he is not on the pitch. Leinster will try and go after the Quins scrum – it's a lot more solid when Marler's around – and Ross will be the central figure to that.

Trivia: Played for Harlequins against Leinster in the infamous 'Blood-gate' match in 2009.

BREAKDOWN BATTLE

CHRIS ROBSHAW

Position: Openside flanker

Age: 28

Height: 1.88 (6'2")

Weight: 102kg (16st)

Caps: 32 (2 tries)

Why he's so important? The England captain is a formidable operator at the breakdown.

Harlequins crave quick ball to release their backs and also to allow scrumhalf Danny Care to be a factor in breaking around the fringes of ruck and maul.

Trivia: He has completed a barista course as he likes to take a hands-on approach where possible in a business which he owns with a friend, a coffee and wine shop called Black, White and Red.

DOMINIC RYAN

Position: Openside flanker

Age: 24

Height: 1.91m (6'3")

Weight: 98kg (15st 6lbs)

Caps: 1

Why he's so important? Probably going to have to tweak his role to try and be more of a nuisance over the ball at the breakdown. Hits really hard in the tackle, is an aggressive ball carrier and his speed and athleticism allow him to track line-breaks by backs

Trivia: Nicknamed 'Dippy' he has played a whopping 20 times for the Ireland Under-20 team including winning the 2010 Six Nations.