Late goals from Robin van Persie and Andrey Arshavin saw Arsenal beat Olympiacos at Emirates Stadium on Tuesday but it was so nearly a night of frustration for Arsène Wenger's side.
The Greek champions kept their hosts at bay for 78 maddening minutes. Arsenal were always on top but a mixture of visiting keeper Antonis Nikopolidis and some profligate finishing maintained the stalemate.
Frustration was just taking over when the deadlock was broken. The excellent Cesc Fabregas fed Eduardo on the left and Van Persie converted from close range. With four minutes remaining, Arshavin completed the scoring with a cheeky backheel from the Spaniard's pass.
All in all, it was a pleasing night for Wenger's men. They now have six points from two games and are in control of Group H.
But this had been a game of patience.
Wenger made two changes from Saturday. As against Standard Liege on Matchday One, Emmanuel Eboue came in for Bacary Sagna at right back.
Meanwhile Tomas Rosicky replaced Nicklas Bendtner on the right. The Danish striker was feeling the effects of a minor car crash over the weekend.
Olympiacos had Olof Mellberg, Emirates Stadium's first goal-scorer, in their line-up and Zico as manager. Of course, the Brazilian had a super-stellar playing career, far outstripping his opposite number tonight. But, on the strength of this evening's one-way affair, Wenger was in charge of the better team.
There were scares for both keepers in the first 15 minutes. Olympiacos striker Vassilis Torosidis nearly caught out Vito Mannone with an impudent chip from the right flank. Fortunately for the Italian the effort drifted wide.
Shortly afterwards Arshavin tried to find Rosicky at the back post and Antonis Nikopolidis, rather cackhandedly, palmed the ball away.
It was the start of a busy night for the grey-haired keeper.
On the quarter-hour, Fabregas thumped a cross-field ball to Clichy, whose instant control allowed him to breeze past his marker and reach the byline. The Frenchman cut the ball back and Arshavin's low first-time shot was saved by the stretching Nikopolidis
Then, in the 17th minute, Fabregas conjured the ball between his feet and juddered the bar with a shot from the edge of the area. Van Persie collected the rebound and set-up Rosicky who forced a full-length save from Nikopolidis.
A couple of minutes later, some trademark Arshavin trickery allowed him to prod a shot towards goal. Nikopolidis turned the ball aside.
Midway through the half, Fabregas was again denied by Nikopolidis. This time he shovelled his shot away.
It started to look like the Euro 2004 winner was the only thing standing between Olympiacos and a drubbing. The Greek champions were now looking devoid of attacking intent.
In the 32nd minute, Van Persie threaded a corner through the penalty area and Thomas Vermaelen timed his run, escaped his marker then somehow failed to convert. A head-in-hands moment for the free-scoring Belgian defender.
A header from Torosidis reminded the Arsenal defence that he was still around but Van Persie ran straight up the other end fired a rising shot over the bar.
Five minutes before the break, the Dutchman, rather aptly, Cryuff-turned his marker one way then the other before seeing his shot saved at the near post by Nikopolidis.
As the whistle approached, the keeper tipped a free-kick away from Vermaelen and Diaby nudged a header past the far post. It had been all Arsenal for the last half-hour.
Olympiacos needed an overhaul at the break. Zico settled for one change - Ieroklis Stoltidis for Jaouad Zaïri. It seemed to help.
In the opening minutes the visitors fashioned their first real chance.
Dudu swung over a corner from the left, Mellberg won a header on the edge of the six-yard box and Mannone palmed the ball off the toes of Torosidis.
It would have been much more than a sucker-punch had it gone in and Arsenal retorted.
In the 52nd minute, Fabregas won the ball in midfield and Eboue fed Van Persie on the edge of the area. Nikopolidis spilled his initial shot and, as Michal Zewiakow mopped up the rebound, the Dutchman slid in. He earned a booking for his trouble.
Arsenal continued to attack. Diaby's cut back just failed to find Arshavin then Arsenal had claims for a penalty when Dudu appeared the bat the ball down. However frustration was starting to rise.
Wenger brought on Eduardo for Rosicky after 66 minutes as Arsenal re-doubled their efforts.
It was a scene that had been played out so many times in the first season at Emirates Stadium. Arsenal - on top, in control and slightly desperate - chasing a goal when they should be way in front.
In the 73rd minute, Van Persie was again denied by Nikopolidis and Gallas was flagged offside as he attempted to turn in the rebound.
Just before Wenger threw on another striker, Diaby was denied twice - once when Nikopolidis diverted his shot around the post and then, from the corner, when his shot was blocked from close-range.
The Frenchman then made way for Carlos Vela. The Mexican's entrance was followed closely by the opener but he had nothing to do with it.
Fabregas threaded a ball to Eduardo in the left channel. He waited for his moment then weighted his pass into the area. Van Persie arrived on cue to sweep the ball home from close range.
Olympiacos physically slumped. They raised themselves for a final rally but were finally sunk by Arsenal's second four minutes from the end.
Fabregas sent over a low ball from the right and Arshavin clipped a backheel past the keeper.
It was a happy end to a game that, for long periods, had Arsenal fans tearing their hair out.