GLASGOW (AFP) - Celtic kick-started their Champions League campaign with an impressive 2-1 victory over Ajax in Glasgow on Tuesday.

The Dutch side had seen Christian Poulsen cannon a shot off the post before James Forrest showed nerves of steel to convert a 45th-minute penalty after Anthony Stokes had been fouled by Stefano Denswil.

Celtic had 'keeper Fraser Forster to thank as he denied Thulani Serero the chance to equalise just a minute before Beram Kayal extended the Scottish champions' lead in the 54th minute with his first goal since 2011.

Substitute Nir Biton was shown a straight red card in the 88th minute for a late challenge on Serero shortly after coming on to make his Champions League debut before sub Lasse Schone pulled one back for Ajax deep into stoppage time.

The win sees Celtic claim their first points of the campaign and they move up to third in Group H, just two points behind AC Milan, who drew 1-1 with table-toppers Barcelona.

It proved to be an unhappy return to Glasgow for Ajax manager Frank De Boer - who had lost both his previous matches at Parkhead as a player during his brief spell with Celtic's fierce rivals Rangers in 2004 - with his side now languishing at the bottom of the group with just one point.

Celtic manager Neil Lennon said victory had given his side a great chance of qualifying from the group.

"Ajax are an excellent side and I said before the game they would give us as many problems as Barcelona and Milan and that proved to be the case," he said.

"But I think as the second half wore on we got better and better and I thought we thoroughly deserved to win the game and it leaves us in a very good position." De Boer felt the better side lost.

"I have mixed feelings about the result. Celtic didn't create anything.

Although they scored twice one was a penalty and the other one wasn't really a chance.

"We dominated the game but we only scored one goal. We should have equalised and then moments later it was 2-0 so I am very disappointed." Ajax gradually began to impose themselves on the match with Viktor Fischer flashing a shot wide before Siem de Jong fired into the side netting.

The Dutch champions came within a whisker of opening the scoring on the half-hour mark as Fischer's free-kick caused panic in the box before breaking to Poulsen, whose first-time shot crashed off the base of the post.

It didn't look like anything would separate the sides going into the break before Stokes earned his side a 45th-minute penalty when Denswil brought the Irishman down in the box.

After a lengthy delay that saw Poulsen and Celtic's Virgil van Dijk booked for dissent, Forrest showed nerves of steel to step up and lift the ball over Jasper Cillessen, sparking ugly scenes among the large travelling support, who appeared to throw seats at stewards.

Ajax had a great opportunity to equalise in the 53rd minute when Serero played a neat one-two with Kolbeinn Sigthorsson but his shot was superbly stopped by Forster.

The Amsterdam giants were left to rue that miss a minute later when Kayal doubled his side's advantage.

A shot from Samaras was blocked but broke to the Israeli international 20 yards out and his low drive took a slight deflection off Denswil in a crowded penalty box before sneaking into the bottom corner.

Ajax came close to reducing the deficit in the 56th minute when Ricardo van Rhijn's driven shot into the box broke to Sigthorsson, whose first-time effort whistled inches wide of Forster's left-hand post.

Biton's red card could have been costly but it came so late on that Schone's superb strike from 20 yards pulled one back for Ajax was all the Dutch could show for their efforts.