Scott McDonald on Everton-linked Kieran Tierney's future at Celtic

Allan Campbell of Motherwell vies with Kieran Tierney of Celtic during the Scottish Cup Final between Celtic and Motherwell at Hampden Park on May 19, 2018 in Glasgow, Scotland.

Kieran Tierney is said to be interesting both Everton and Manchester United.

Kieran Tierney of Celtic celebrates with the Scottish Cup Trophy following the Scottish Cup Final between Motherwell and Celtic at Hampden Park on May 19, 2018 in Glasgow, Scotland.

Former Celtic striker Scott McDonald has told BBC Sport that he believes Kieran Tierney could remain with the Scottish champions until the summer of 2020 - frustrating four Premier League sides.

Tierney, 21, managed 55 appearances in all competitions for the Hoops last season, scoring four goals and turning provider a further 11 times as he proved crucial in Celtic's second successive treble.

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Reports have suggested that Everton are interested in Tierney, as well as Bournemouth and Wolves for a fee of £25million (Daily Express), while Manchester United are said to be long-term admirers of the Scotland international.

Kieran Tierney of Celtic celebrates as Celtic win the Ladbrokes Scottish Premier League during the Scottish Premier League match between Celtic and Aberdeen at Celtic Park on May 13, 2018...

But McDonald reckons Tierney could frustrate the Premier League sides that are said to be interested in the Hoops academy product by remaining at Celtic for another two years.

"I think he might possibly just stay on for even another year, maybe two more," McDonald said.

"If they're offering the amounts of money that can be offered down in England then it would be a huge temptation but we've seen in the past how much he loves the football club and he's still only young.

"If he holds out another year or two, I think opportunities do open up. Someone like Man United, that has been touted with the struggles that they have found at left-back."

Scott McDonald of Celtic goes to ground and is awarded a penalty during the Wembley Cup match between Celtic and Al Ahly at Wembley Stadium on July 24, 2009 in London, England.

Tierney, a boyhood Celtic fan, has five years remaining on his current Celtic contract but fans are beginning to fear that at his young age, he is starting to outgrow the Scottish Premiership.

With the defender stating in the past that he wants to play at the highest level possible, it may see him leave for the Premier League but McDonald reckons the Premier League quartet will be frustrated for at least this summer.

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