Ronald Koeman believes Old Trafford is the perfect stage for Romelu Lukaku to banish his derby disappointment and demonstrate he does deliver against the Premier League’s strongest sides.

The Everton manager has spoken to the Belgium international about his meagre contribution to the defeat at Liverpool on Saturday, citing the fact that Lukaku and Ross Barkley were “not at their level” as a reason for his young team’s 3-1 reverse. Lukaku tops the Premier League’s goalscoring chart this season with 21 but has often struggled to have an impact against the top teams, with only four of his 39 league goals over the past two campaigns arriving against the current top six.

Koeman claimed poor service and fatigue following Belgium’s midweek friendly in Russia were to blame for Lukaku’s anonymous display at Anfield. He said the striker accepted his contribution was not up to standard.

“Rom really thinks a lot about football and he’s really honest in his performances, but we had maybe three or four times a counterattack where our final ball was not good,” the Everton manager said. “The free-kick from Ross, the back post to Ashley [Williams] – if he hit the ball good then Rom would score and the whole story is different. Also as a striker you need support, you need assists, but I think his work rate and his freshness was not 100%.

“He knows himself when it’s good and when it isn’t good like last Saturday when he was not performing what he can do and what the teams needs. But it’s difficult. In the international week he was travelling back from Russia at 5am in the morning. He’s a human being. I don’t criticise him and if I need to criticise I will do it one-on-one.”

Koeman must select from the same injury-hit squad for Tuesday’s game at Manchester United but insists Old Trafford offers the perfect opportunity for Everton to recover from the derby.

He said: “The next step is if you go to teams like United and to stadiums like Old Trafford and be yourself. Go to them and be yourself, be confident in yourself; believe in the gameplan, believe in our qualities and how difficult we can make it for those strong teams.

“That’s one of the reasons I was proud [against Liverpool] – because we weren’t afraid. The start was fantastic and the first shot was 1-0 and the reaction was what I like. It was not about us having injuries, we had reasons to break down but no, we were strong even with young players and we showed it on the pitch. It’s not the final result that everyone likes but if I see my team come out of the dressing room against United and play how we like to play, then I am proud.”