Boyhood Villa fan Smith guided the Midlands outfit back to the Premier League, whilst Lennon ensured the Hoops continued their dominance in Scotland's top-flight by securing the treble.
Now, with the summer transfer window in full swing, both managers are extremely busy in trying to recruit players, with Lennon keen to solve one problem area in his team – right-back.
Well, the Northern Irishman should look no further than Villa's Bree, who was on-loan at Ipswich for the second half of last season.
The 21-year-old is currently behind Ahmed Elmohamady at Villa Park, and with new signing Fred Guilbert also joining from France, he could find himself being the third choice under Smith upon their Premier League return.
Simply put, Bree is too good a player to be the third choice, and given the competition ahead of him now, he more than likely might find himself having to find regular football for next season.
Celtic would be the perfect place for the attack-minded fullback, whose strengths are powering up and down the flank, being strong on the ball and picking out quality passes.
He would also be a reliable player for the Bhoys and considering his current status at the club, they might be able to pen him down on a permanent contract.
Since moving to Villa in 2017, Bree has had to deal with a number of injuries, hence his career has not been able to push forward.
Last season, prior to going to Ipswich, when he was fit, he was thrown straight into the deep end and had to fill in at centre-back for the club because no-one was fit and available.
Despite just coming back from injury, the youngster, for a number of games during the winter period, filled in at centre-back and showed calmness and maturity beyond his years. Once again, this would be very useful to Celtic and Lennon.
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