Hearts manager Craig Levein has criticised "crazy" attempts to dictate maximum length of grass in Scottish football and vowed to be unmoved by Brendan Rodgers' criticism of the Tynecastle pitch.

The Celtic boss, whose side travel to face Hearts on Saturday, claimed he was "embarrassed" by the length of the grass during his side's 3-1 win in Edinburgh in May and argued "that wasn't football" after his team adopted a direct approach to overcome the issue.

Hearts installed a new pitch over the summer but when asked how it was shaping up, Levein said: "It's a bit long just now, that's all I can say."

And he criticised unsuccessful attempts to instigate a rule on length of grass, which was defeated at last month's Scottish Professional Football League annual general meeting.

"There is a genuine issue, particularly on the likes of our own park this summer," the former Scotland manager said. "We spent a lot of money to re-seed it and do a hell of a lot of work on it.

"And when the grass is young, as ours is, then sometimes you need to have length in the grass to protect it.

"So I think it's crazy to dictate to the groundsmen what length the grass should be when they are doing their best to protect the club and their pitch."

In the immediate aftermath of Rodgers' criticism in post-match interviews, Levein declared the Celtic manager could "bleat and moan all he wants, it will be the same again next season".

And he reiterated he would be unaffected by the comments ahead of Saturday's Ladbrokes Premiership encounter.

"I sat with Brendan after the game in my office and he never mentioned the pitch at all," Levein said.

Rodgers has bigger concerns than the Tynecastle grass after his side were held to a 1-1 draw by AEK Athens in the third round of their Champions League qualifying campaign on Wednesday.

Celtic now face a major challenge to maintain their qualifying hopes when they play in Greece on Tuesday and Levein hopes to capitalise on the timing of his team's meeting with the champions.

"I was at the game in Glasgow and although Celtic dominated for long spells they probably ended up with a result that isn't ideal," he said.

"And we have found ourselves in a position of being the game in between probably their two most important games financially anyway for a little while. We will try and take advantage of that."

When asked if Celtic might be casting eyes to Athens, Levein said: "I hope they are. Brendan and his team are professional enough to try and not let that happen but I think it's quite natural, understanding how important getting through this round would be for Celtic."