You would think that the ascent to second place in the Guinness Premiership would be viewed as a momentous feat for Harlequins, who, only two seasons ago, were playing their rugby in National League One. Asked to sum up the achievement for his young side after this comfortable win, Dean Richards, the director of rugby, looked surprised. “We're in second, are we?” he asked. “That's quite high.”

Whether his indifference was genuine or not is another matter, but Richards insists that league position is irrelevant this season and that their progress is to be judged on performances rather than points. Their target for this season was merely to improve on last year's seventh-place finish.

Nevertheless, having won seven of their past eight Premiership games, a bonus-point win leaves Harlequins two points behind Gloucester, the leaders, with three games remaining.

“I'll be delighted if we make the play-offs, but if we don't, we don't,” Richards said. “We've got London Irish away, Sale at home and Leicester away in our last three games, so we're not getting ahead of ourselves. But things are going well.”

On a heavy pitch, which had been drenched by overnight rain, a scrappy contest was inevitable and it took Harlequins until the final play of the game to clinch their bonus point. The crucial try was made by a 50-metre burst from George Robson, the lively 22-year-old lock, who bounded over several weary Leeds Carnegie defenders as though they were speed bumps littering his path.

Robson was finally hauled down just short of the line, but the ball was quickly recycled, enabling Will Skinner to dive over.

That fourth try came as a great relief to Harlequins and, in particular, to David Strettle. The England wing, who had come off the bench early in the second half, was making his first appearance since suffering a foot injury in the match against Wales ten weeks ago.

In the 76th minute, he made a surging break from his own 22, carried the ball deep into the Leeds half and had only to draw his man and pass accurately to put De Wet Barry in the clear. Alas, his pass was a good three yards forward. Strettle hung his head in shame.

For all the dominance of the Harlequins pack, Leeds remained in the game throughout the first hour. They conceded just one try in the first half, when Mike Brown leapt to catch Adrian Jarvis's cross-kick, and only in the final quarter did Harlequins translate their power into points.

In the 53rd minute, Danny Care took a tap penalty after Leeds had been penalised at the scrum and darted over from short range. Fourteen minutes later, Jim Evans plunged over after Nick Easter, another England international who emerged from the bench, had made good ground from a lineout.

Care had again shown his attacking potential from scrum half, gliding across the turgid surface where others were getting stuck in the mud. “If England take three scrum halves to New Zealand this summer, I'd have thought he'd be one of them,” Richards said.

For Leeds, the looming certainty of relegation has been avoided for another week, but a visit to face Gloucester at Kingsholm next week is likely to confirm their demotion.

Whereas Harlequins have profited since their promotion from League One, Leeds will shortly return whence they came.

“I know what it's like to be in National One, to come up to the Premiership and sustain your place, and then to go on from there,” Stuart Lancaster, the Leeds director of rugby, said. “A lot of credit should go to Harlequins for doing that.”

Scorers: Leeds Carnegie: Penalty goals: Di Bernardo 2 (17min, 46). Harlequins: Tries: Brown (17), Care (53), Evans (68), Skinner (80+5). Conversions: Jarvis 3. Penalty goals: Jarvis 2 (4, 37).

Scoring sequence (Leeds first): 0-3, 0-8, 3-8, 3-11 (half-time), 6-11, 6-18, 6-25, 6-32.

Leeds Carnegie: L Hinton; R Welding (rep: A Greendale, 73), R Vickerman, A Tuilagi (rep: L Burrell, 60), T Rock; A Di Bernardo, J Bedford (rep: D Edwards, 68); M MacDonald, V Ma'asi (sin-bin, 28-40+1; rep: R Rawlinson, 68), A Hopcroft (rep: F Pala'amo, 53), P Bouza (rep: E Lund, 53), S Hooper, R Oakley, H Fourie, C Clark (rep: Rawlinson, 35-40+1; rep: A Balding, 53).

Harlequins: M Brown; T Williams (rep: D Strettle, 53), U Monye, J Turner-Hall (rep: DW Barry, 72), S Keogh; A Jarvis, D Care (rep: A Gomarsall, 64); C Jones (rep: J Brooks, 71), T Fuga (rep: G Botha, 53), M Ross, O Kohn (rep: J Evans, 53), G Robson, C Robshaw, W Skinner, T Guest (rep: N Easter, 65).

Referee: D Richards.

Attendance: 3,854.