Mark McCall viewed Saracens' 22-12 Aviva Premiership victory over Harlequins as a wake-up call for next weekend's European showdown against Wasps.
The reigning English champions and league leaders ran in three first-half tries on Saturday but could only add one Owen Farrell penalty to their score after the interval, despite dominating the match.
They face in-form Wasps in Saturday's Champions Cup semi-final at the Madejski Stadium and McCall knows an improved performance will be needed against a team that has rocketed up the Premiership into second place.
"It wasn't about missing out on the bonus point, more about how we played. It was a patchy performance, but it is a kick up the backside for Wasps," director of rugby McCall said.
"This game and last weekend's against Northampton are below the standards we'd expect.
"We weren't good in some areas and were a bit loose. We made in-roads into Quins but then threw the ball away. We weren't patient enough.
"Our penalty count was that of a losing team and a third of them came at scrum time, so that is something we'll have to fix for next week.
"We scrummed magnificently against Northampton last weekend and we were the opposite of that in this game.
"It's difficult to ask the players to keep fronting up week on week, but Wasps is a massive game and the players are already talking about it in the changing room."
Watch Saracens take on Wasps live on Sky Sports 1 from 3pm, Saturday 23 April. Catch all the action for £6.99 with a NOW TV day pass.