Hull cruised to a comfortable victory over Harlequins but their coach, Richard Agar, saw his Wembley preparations hit by a double injury blow. Matt Sing, the wing, faces a race against time for next week’s Carnegie Challenge Cup final after it emerged he suffered a leg injury on Thursday while Motu Tony, the full-back, was carried off midway through the second half clutching at his knee.

“Motu’s a little bit of a concern at this moment in time,” Agar admitted. “We left Matt Sing out as a precaution. We didn’t feel it was necessary to risk him tonight.”

Despite those problems, Agar will have been buoyed by his side’s demonstration of the defensive tenacity they will need to trouble table-topping St Helens. They led 14-0 at halftime and their victory was never really in doubt after Ewan Dowes, the prop, scored his first try in 89 games after just seven minutes. Danny Tickle added a penalty to stretch the advantage before Tony pounced near the line when Rikki Sheriffe, the Harlequins wing, fumbled Danny Houghton’s smart kick to the corner.

Harlequins struggled to find any fluency and failed to produce a cutting edge on the odd occasions that they made incision into Hull’s defence. Their lack of finishing was punished further when Graeme Horne dived over from close range and Kirk Yeaman, the centre, added the finishing touches to an encouraging display. Chris Melling scored Quins’ only try after supporting David Howell’s break in the closing moments.

“If Richard Agar wanted a performance, he got one,” Brian McDermott, the Harlequins coach, said. “We challenged them on their try-line but they got there and defended. I think Richard will sleep easier knowing his team have got a bit of bite.”

Scorers: Hull: Tries: Dowes, Tony, Horne, Yeaman. Goals: Tickle 4, Radford.

Harlequins: Tries: Melling. Goals: Purdham.

Teams: Hull: M Tony; T Briscoe, T Byrne, K Yeaman, G Raynor; D Washbrook, T Lee; P Cusack, S Berrgian, E Dowes, W Manu, D Tickle, L Radford. Interchange: D Houghton, J Thackray, G Horne, S Wheeldon.

Harlequins: J Wells; W Sharp, T Clubb, D Howell, R Sheriffe; S Hill, D Orr; G Haggerty, C Randall, D Ward, K Temata, J Grayshon, R Purdham. Interchange: C Melling, D Williams, L McCarthy-Scarsbrook, J Rinaldi.

Referee: T Alibert (France).