Barry (left) scored the winner to earn Villa three points in Group F
Gareth Barry struck the winner as Aston Villa produced a solid performance to overcome Ajax in Uefa Cup Group F.
Ajax made a lively start but Villa took the lead against the run of play when skipper Martin Laursen powerfully headed in Ashley Young's corner.
The hosts were pegged back when Urby Emanuelson's corner was headed in off the bar by Thomas Vermaelen.
But Barry got the winner when he coolly slotted in after being picked out by Ashley Young's cutback.
Ajax started strongly, passing the ball around superbly and pushing Villa back, but they failed to really create anything and were soon made to pay.
When Villa suddenly kicked into life and forced a corner, Young's excellent delivery was powerfully headed in by Laursen, who got to the ball ahead of stranded keeper Kenneth Vermeer.
The goal boosted Villa and there was now far more bite to their tackle and zip about their passes as they began to dominate their opponents.
But, as Ajax had earlier, Villa could not fashion any clear chances and they were caught by a replica of the sucker punch they had delivered to the Dutch side.
Emanuelson swung in a corner and the unmarked Vermaelen thumped home a header which went in off the underside of the crossbar.
There was a fine balance about the game, with Villa enjoying the edge physically but Ajax showing speed and guile in their counter-attacks.
Jeffrey Sarpong and Luis Suarez looked slick and dangerous coming forward for the visitors, while Villa's main threat came from Young.
It was through their left winger that the hosts gained the upper hand when he cut the ball back for Barry to clip into the bottom corner from 15 yards.
A spell followed when Villa looked certain to add to their advantage, and only a decent double save by Vermeer kept them out - even though the keeper did almost carry Laursen's header over the goal-line.
Martin O'Neill's men were then twice denied a penalty as first Young's cross appeared to hit an Ajax hand and then Gabriel Agbonlahor tangled with Leonardo.
Villa were in control but they almost found themselves caught out when an Ajax break ended in a well-struck Emanuelson short that forced Brad Friedel into a smart save.
The hosts survived that scare but did suffer a blow late on when Agbonlahor was stretchered off after a clash with keeper Vermeer.
Aston Villa manager Martin O'Neill:
"We were terrific and fought back magnificently to get ourselves back in front after their equaliser.
"In the second half we pressed them higher up the pitch and we took the ball off them.
"They are a good side and pass very well indeed but we have excellent players and that should not be forgotten."
Aston Villa: Friedel, Luke Young, Cuellar, Laursen, Shorey, Reo-Coker, Petrov, Barry, Milner, Agbonlahor, Ashley Young.
Subs Not Used: Guzan, Sidwell, Harewood, Davies, Knight, Salifou, Gardner.
Goals: Laursen 8, Barry 45.
Ajax: Vermeer, Silva, Oleguer, Vermaelen, Emanuelson, Lindgren, Sarpong, Vertonghen, Suarez, Huntelaar, Gabri.
Subs Not Used: Vonk, Van Der Wiel, Cvitanich, Leonardo, Sno, Anita, Schilder.
Goals: Vermaelen 22.
Ref: Thomas Einwaller (Austria).
BBC Sport Player Rater man of the match: Aston Villa's Ashley Young 7.71 (on 90 minutes).
Please note that you can still give the players marks out of 10 on BBC Sport's Player Rater after the match has finished.
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