Harlequins Director of Rugby Conor O'Shea was full of praise for his side's mental resolve after they battled past Connacht on Friday.

The English Premiership leaders took a 10-game winning run into Europe's premier club competition but they almost came unstuck against the Heineken Cup newboys.

Quins needed a brace of penalties from Nick Evans in the final three minutes to seal a 25-17 success at the Stoop after Connacht cut the gap to just two points with a quarter of the match remaining.

And while Quins' free-flowing approach has rightfully earned them plenty of plaudits so far this term, it was their determination not to buckle under intense pressure that was the standout feature for O'Shea in the Pool Six opener.

"We were tested big time but we had the fortitude to come through," said O'Shea after Nick Evans kicked 20 points as Quins celebrated their 50th match in the European Cup with a sixth win over Connacht in seven attempts.

"Mentally it was tough. We could potentially have gone 26-10 up early in the second half but we had a try disallowed for blocking and then we were back to a one-score game at 19-17 and were defending and defending hard. They played really good rugby in the second half but mentally our guys are very strong.

"Once or twice, we could have got away but we didn't. They started dominating possession and we couldn't get our hands on the ball and when we did we turned it over.

"I'll give a massive amount of credit to them but I'm delighted that we showed that sort of mental strength. It's easy to be offloading away and pirouetting down the pitch but sometimes you have to roll up your sleeves and come up with the goods, and we did."

Connacht may be the unknown package in the pool as far as European Cup pedigree is concerned but no one at Harlequins had any intention of taking the Galway-based outfit lightly, even if outside observers may have been predicting a handsome home win.

The two sides have met regularly in the Challenge Cup and former Ireland full back O'Shea knows all about opposite number Eric Elwood and the nature of Connacht.

O'Shea insisted he and his charges were fully aware of the size of the battle ahead of them and a win of any sorts was a welcome way to mark their return to the competition following their Amlin triumph last term.

"That was Connacht's first game in the European Cup and, with the physicality they have, we knew exactly what was coming," added O'Shea.

"I had a massive amount of respect for them before the game and I have a massive amount of respect for them after the game.

"They came at us full metal jacket and you could say we got a little flustered at times but, no one in our dressing room is arrogant enough to think that you get things for free.

"This is the European Cup, it was their first game in the competition and we got exactly what we expected. It was physical, it was tough at the breakdown, but we found a way to win.

"It's great to be back in the European Cup - that was proper rugby. It's good to see people down in the dumps over winning. It was tense out there, but they're the matches you have to win."