Arsene Wenger expressed his delight at Mesut Ozil's new-found attacking confidence after Arsenal's 3-0 Champions League victory over Dinamo Zagreb on Tuesday.
Ozil broke the deadlock at the Emirates Stadium before Alexis Sanchez netted a brace, as Arsenal kept their hopes of qualifying for the last 16 alive.
The duo - along with Joel Campbell - proved a constant menace to the Dinamo defence, with Sanchez having provided the assist for Ozil's opener.
And Wenger singled out the Germany international, who has now been involved in 11 goals in his last nine Arsenal matches, for individual praise during a post-match interview.
"He had an outstanding first half," Wenger told BT Sport.
"I've never seen him in the box so many times this season, especially in the last five or six games."
Arsenal now need to beat Olympiacos by at least two goals to guarantee their place in the next round.
"It was a good night because we did the job and played at a high pace," added Wenger.
"We wanted to be in with a chance and now it's down to how we do at Olympiacos.
"It promises to be a very interesting game."
Arsenal, who sit third in Group F heading into the final round of fixtures, are now assured of a place in the Europa League should they fail to deliver in Greece in a fortnight, but Wenger stressed: "That's not the target. Let's give everything to stay in the Champions League."