Mark McCall admitted Saracens had to dig deep in their 29-20 Champions Cup quarter-final victory over Northampton at Allianz Park.
England wing Chris Ashton crossed in the 69th minute to finally put the tournament favourites in control before Chris Wyles produced a late try to sweep the game beyond Saints’ reach.
“In the first half we didn’t play anywhere near to the level that we can,” director of rugby McCall said.
“We just needed to find a way to turn the energy of the game around. Give Northampton a lot of credit because they put us under all sorts of pressure at the breakdown.
“Good teams find a way of getting the job done. We were nowhere near our best and the last few weeks in the Premiership were almost too easy for us in a way.
“These games are different, there’s a lot at stake. This was the first game of the season where it’s on the line and if you lose, you’re out of the competition.
“Maybe we played not to lose a bit, and we were lucky to be only four points down at half-time.
“We know we’ll have to improve a lot of things against Wasps in the semi-finals.”
Meanwhile, Wasps boss Dai Young described his team’s dramatic late quarter-final victory over Exeter as “great theatre” after goalkicker Jimmy Gopperth held his nerve amid unbearable tension.
Fly-half Gopperth landed a nerveless match-winning conversion with the final kick of an epic Ricoh Arena clash as Wasps edged through 25-24 and secured a last-four place in top-flight European competition for the first time since 2007.
“It was great theatre at the end for the supporters… It was a great game that could have gone either way. A semi-final in Europe can’t be scoffed at. We are going to play another English team, which is going to be another battle for us, but we will worry about that when it comes.”
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