MK Dons defender Gary Mackenzie has penned a new contract which will keep him at the club until 2013.
The 25-year-old, who was in the final year of his current deal, has helped the Dons keep four clean sheets during their ascent to the top of League One this season.
Mackenzie said he was happy to commit his future to the club, saying: "When I signed I was told the club would move forward, and we're certainly going in the right direction. I hope we can push on for promotion from here."
Dons' Manager Karl Robinson said Mackenzie had been in incredible form.
"Somehow he manages to improve week in, week out and he never gives anything less than 100 per cent," he said.
"A lot of clubs will be envious, and I am delighted he believes in the ambition of the club."
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