The 20-year-old has spent the last year gaining valuable experience with SkyBet League One outfit Notts County.
Now after blasting 14 goals in 40 appearances for the Magpies as Shaun Derry's side beat off the threat of relegation in a dramatic last-day decider with Oldham, McGregor believes he is ready for top-team action with the Hoops.
Celtic are currently on the trail of a new boss to replace Lennon but McGregor hopes whoever comes in has an open mind as to his potential.
The Scotland Under-21 cap, in Billy Stark's squad for Wednesday night's European Championship qualifier with Holland, said: "The fact the club are changing managers will make it difficult but I'm definitely determined to come back again next year and try to break into the team.
"I've had a good season so now I want to take that back with me to Lennoxtown and do everything I can to earn my place.
"Everything was positive under the old gaffer. Every time I spoke to him or heard from my agent, the feedback I got was good and was all geared towards him having a good look at me during pre-season.
"But maybe now the person who comes in might want to put their own stamp on the team and that could allow me to progress into the first team.
"I will just have to go back and work hard."
A number of former Parkhead players have been linked with Lennon's old post, including Malky Mackay and Paolo Di Canio.
But McGregor knows who his favourite would be.
"There have been a lot of big names linked to it and Henrik Larsson is probably the biggest," he said. "He's a club legend and it would be a great opportunity if he did get it.
"But when I go back in June, hopefully I can impress whoever gets it."
Stark says the Scots youngsters need three wins from their final three qualifiers against Holland, Luxembourg and Slovakia if they are to reach next year's finals in the Czech Republic.
However, they were hammered 4-0 the last time they faced the Dutch but McGregor has told his team-mates not to shy away from the challenge.
Speaking ahead of Wednesday's clash at St Mirren Park, he said: "We have done a lot of video work on Holland, so we know what to expect.
"But we have got to be confident in the players we have and believe we can beat them."