Despite Racing try-scorer Kitione Kamikamica being sent off in the Round 2 clash at Twickenham Stoop, the Gallagher Premiership club couldn’t extend their advantage and had to be content with a 14-10 victory.

In fact, Racing threatened the Quins line on several occasions as the hosts made a string of handling mistakes attempting to run the ball out in torrid conditions.

“It wasn’t the prettiest and we were probably lucky, to be fair,” Matson said. “We did our best to ruin that. The conditions were poor, but we made some poor calls.

“For all that, we’re back in the hunt for the knockout stage again after getting the four points. Getting the win was the most important thing, but there’s a lot to review.

“We tried to play way too much and that’s a good learning for us at this time of year, because at the end of December there’s more of that type of rugby to come. Ultimately, we move forward in Europe and that’s the key thing.”

One aspect Matson was pleased with was Quins’ stifling of Racing talisman Finn Russell, the Scotland fly-half who is set to join Bath Rugby ahead of next season.

“We knew that he would be a key guy, because he can control the ball really well,” Matson said. “It wasn’t really an attacking game, but a lot of their territory battle is won by him.

“He still had a great game, even in these conditions. The old Scots know how to put the ball behind you. He did a really good job, but we cornered him a couple of times.”

Quins will need to keep Russell quiet again in Round 3, as they face Racing at Paris La Defense Arena on January 15.

Harlequins head coach Tabai Matson believes his side are back in contention for qualification for the Heineken Champions Cup knockout stage, after almost squandering the chance to record their first win of this season’s competition against 14-man Racing 92 last weekend.