The double winners crushed understrength opposition with the line-out drive their primary weapon as hooker Jamie George and prop Richard Barrington claimed two tries each to continue the countdown to the European quarter-final against Leinster.
Only three games remain before Saracens play the match that gives meaning to their season having been relegated from the Premiership for persistent salary cap breaches and McCall insisted they are not where they need to be.
“It was a bit patchy from us. We did some good things but we didn’t sustain the good things,” the director of rugby said.
“At half-time we were disappointed with how we had defended in the first half. We wanted to step that up and we did. We were very difficult to play against in the second half and that’s the type of team we want to be.
“Our line-out drive hasn’t gone so well but it went much better. In general when we had good field position in the 22 we came away with a lot of points and that was encouraging because it’s one of the things we’ve talked about.
“We’re definitely not quite where we need to be for the Leinster game, although individually some of our players are playing really well.
“We’re building towards that and to play a game like this which has less meaning, it will always feel a little bit different.”
McCall revealed that fly-half Owen Farrell and prop Mako should recover from respective thigh and back injuries in time to face Wasps on Saturday, which he said would be treated as the final run-out for his first-choice 15 before Leinster.
Irish picked nine academy representatives in their side and paid the price as Saracens raced clear despite never hitting top gear.
“With the way the games come, that was our best available team and they didn’t let themselves down individually,” Exiles director of rugby Declan Kidney said.
“They deserved their run and they got more right than wrong. Experience-wise this will only stand them in good stead.
“Saracens are a professional outfit and are proud, they won’t just go through the motions. We managed to score tries and had one or two more opportunities.”
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