Victory over Gloucester, the Guinness Premiership leaders, may have come at a high price for Nick Easter. The Harlequins and England No8 aggravated a knee injury on Saturday and it could mean that he misses England's RBS Six Nations Championship fixture against Scotland at Murrayfield on Saturday. He needed all the ice in Twickenham to allow him to emerge an hour after the match hobbling on a braced left leg. Easter missed the England's defeat by Wales because of the same injury.

“It [the knee] was traumatised before and nothing was done today to make it worse,” Easter said. “It's been all right the last three games. It was touch-and-go for the Wales game. It should be OK, bit of compression and ice and get the swelling down.

“Round half-time the decision was made and I'm like, ‘nah, I am going to stay on.'” From next season, neither Harlequins nor Easter would have the choice, England will forbid him to play. That is the likeliest source of conflict with the de facto centralised contracts coming into effect.

“The body feels a lot better when you've won,” Easter admitted. “We're here to win medals, so there's no point saying we'd be happy with fifth or sixth place because we won't be when we've got a chance of the play-offs.”

“We've [London] Wasps and Bath on international weekends, so they'll lose a couple of players. Ideally, we don't want it to come down to Leicester away on the last game of the season.”

Luke Narraway, the Gloucester No8, who replaced Easter for the match against Wales, did not advance his cause as part of a Gloucester side that allowed Harlequins to exploit their strengths in broken play.

It is Harlequins' third win in a row and arguably Dean Richards's most significant since becoming director of rugby in 2005. Harlequins, with a game in hand, now lie fifth on the Premiership table and are just nine points behind top-placed Gloucester. The visiting side took two bonus points after scoring four tries, but Willie Walker missed five kicks which cost Gloucester 12 points.

Harlequins have beaten Gloucester only once in their past 11 meetings - in February 2001 - and had to come from 20-10 down on Saturday. A try under the posts by Mike Brown on the stroke of half-time, made by another excellent sniping dash round the fringes by Danny Care, England's scrum half in waiting. Brown, the Harlequins full back was far from flawless, but he did not suffer in comparison to Iain Balshaw, who was good and bad in equal measure.

Lesley Vainikolo, had an excellent first half, as Gloucester worked him the ball. He made a try-saving tackle and a try for Balshaw, but Gloucester's other wing, James Simpson-Daniel, who has bulked up, was the most impressive. It came as no surprise that England called him up yesterday with David Strettle injured.

Scorers: Harlequins: Tries: Jones (21min), Brown (40+4), Robson (80+1). Conversions: Jarvis 2, Malone. Penalty goals: Jarvis 3 (15, 54, 73). Gloucester: Tries: Adams (18), Balshaw (23), Allen (36), Simpson-Daniel (57). Conversion: Walker. Penalty goal: Walker (34).

Scoring sequence (Harlequins first): 3-0, 3-5, 10-5, 10-12, 10-15, 10-20, 17-20 (half-time) 20-20, 20-25, 23-25, 30-25.

Harlequins: M Brown; T Williams, H Luscombe (rep: DW Barry, 49), T Masson, U Monye; A Jarvis (rep: C Malone, 74), D Care; C Jones, T Fuga, M Ross, J Percival (rep: G Robson, 40), N Spanghero, C Robshaw, W Skinner, N Easter.

Gloucester: I Balshaw; J Simpson-Daniel, J Adams (rep: M Foster, 40), A Allen, L Vainikolo; W Walker, R Lawson; N Wood (rep: A Dickinson, 70), O Azam (rep: A Titterrell, 52), C Nieto, P Buxton, A Brown, A Strokosch, A Qera (rep: M Bortolami, 64), L Narraway (rep: G Delve, 57).

Referee: S Davey.

Attendance: 12,638.