MONACO -- Red Bull team principal Christian Horner questioned Mercedes' approach to the Monaco Grand Prix, and said the pace at which George Russell ran his race at was "defeatist" in letting the top four drivers get away.
Russell finished Sunday's race fifth, ahead of Red Bull's Max Verstappen in sixth and Lewis Hamilton in seventh.
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All three drivers took the original start on hard tyres, meaning they were left with little choice but to switch to mediums when the race was red-flagged after a first-lap wreck.
Knowing that its best strategy option for retaining fifth place was to run the medium tyres until the end of the race, Mercedes told Russell to monitor his pace, which allowed the four cars ahead of him to open a gap of 15 seconds while Verstappen remained bottled up behind the Mercedes.
Mercedes then pitted Hamilton at the end of Lap 52 to give him fresh tyres and the chance to attack or undercut Verstappen, but did not tell him to push on his outlap, which was critical to putting pressure on the Red Bull.
When Verstappen pitted a lap later he came out comfortably ahead of Hamilton, closed the gap to Russell in fifth but then got stuck again as the Mercedes was able to up its pace after looking after its original medium tyres early in the race.
Ultimately, the top ten cars finished where they qualified, underlining how difficult it is to pass in Monaco, but Horner felt Mercedes should have told Russell to put more pressure on the McLarens and Ferraris in the top four earlier in the race.
"I didn't really understand Mercedes' race today; it was a hugely conservative race by George," Horner said. "To give up so much time and then go so fast at the end of the race, it didn't really make a lot of sense.
"But I don't think it would've changed anything, they weren't going to overtake anybody, it was just a very defeatist race to try and defend fifth."
Unrelated to Horner's comments, Wolff was asked why Hamilton was not told to push harder after his pit stop and admitted Mercedes made a mistake on that aspect of its strategy.
"There was a miscommunication first between us on the pit wall that we got that wrong," Wolff said. "It should have been 'out-lap critical', trying to undercut [Verstappen].
"But then there was a debate whether any out-lap would be enough from the new tyre. So the message he got was at best confusing, but probably wrong.
"It should have been an 'out-lap critical' but the worry in the background was that if we thrashed that tyre in a single lap, then what would happen later.
"But in summary wrong message to Lewis -- this was the team's fault."