John Kingston frustrated as Harlequins defeat to Edinburgh leaves Challenge Cup quarter-final hopes in the balance

Lock Fraser McKenzie burst through the home defence in the first half, and by the time Duncan Weir added two penalties, Quins were staring at a 13-6 deficit at the break.

Allan Dell added to the deficit, and while hooker Joe Gray crossed twice, it wasn’t enough to prevent a rare defeat at The Stoop, 23-18.

That was largely due to an abundance of penalties and three yellow cards conceded, with Kyle Sinckler, James Chisholm and Dave Ward all spending ten minutes in the sin bin.

Quins had lost out in a 71-point thriller between the two teams earlier in the season, though the quality of rugby this time around was not on the same level.

Defensive frailities proved costly as McKenzie found the gaps on numerous occasions in the first half, while Hamish Watson made a break of his own for Dell to add a second after the restart.

But more significantly it left Harlequins no longer on top in their pool, with Edinburgh taking pole position, while a bonus-point victory for Stade Francais against Timisoara Saracens in the rearranged game would see them within two points.

It is France where Kingston’s charges are next to travel, on Sunday, in a potentially do-or-die Pool 5 clash as just three runners-up join the five pool winners in the quarter-finals.

"We talked about discipline at the start of the game," said director of rugby Kingston. "It is hugely important at the moment with the sanctions becoming stronger over the last few weeks and on the day we did not get that right.

"If your discipline is such that you concede that number of yellow cards and play that long with 14 men then you are not going to win."

"We have made it hard for ourselves.

"We don’t deserve to be top of the group, we haven’t done enough. It has put us under pressure to go to Stade and win. We are capable of that and we will do everything we can to make that happen."