OM progressed into the competition's quarter-finals last night thanks to a header in extra time by defender Tyrone Mears, which clinched the French side a 2-2 draw on the night and a 4-3 win on aggregate.

But they were on the back foot for long spells of the match at the Amsterdam ArenA and Gerets was happy to see his players weather the storm.

"They posed us a lot of problems because of their movement and our players didn't stop running," said the Belgian.

"We perhaps ran twice as much as our opponents. We didn't, it's true, find the right balance in our team.

"It is a compliment that I am saying Ajax were the better team. It's the first time we have been in so much difficulty but that is the quality of Dutch football."

Defending a 2-1 lead from the first leg, OM went behind when Eyong Enoh scored just after the half-hour mark but Mamadou Niang put the visitors back in front in the tie two minutes later.

Miralem Sulejmani, with a close-range second-half header, took the last-16 game into extra time but English right-back Mears was the hero in the 108th minute.

"I am very happy to be in the next round," said Mears, who is on loan at OM from English side Derby.

"We showed we have a fighting spirit even though it was hard. And I am so happy to have scored the goal."

Gerets is not bothered who Marseille meet in the last eight, adding: "We will see what happens - I don't have a preferred opponent."