By Dominic Toner

Sunderland are preparing a move for Celtic defender Kieran Tierney, according to a report.

The Express claim that Premier League duo Sunderland and Crystal Palace both sent scouts to watch the 19-year-old in the win 4-0 win over Hearts on Sunday.

It is understood that the Black Cats are weighing up a £10million-plus bid for Tierney and are set to move before the January window closes.

The report details that Sunderland are in need of a new left-back as Patrick van Aanholt looks set to join Palace for £14million.

The Express claim that Celtic are likely to reject any January offers, but could look to sell him in the summer.

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Celtic created history on Sunday as they extended their unbeaten domestic run to 27 games, breaking the 50-year-old record previously held by the Lisbon Lions.

Tierney starred in the victory over Hearts and created two assists.

The young left-back has recently returned to the side after recovering from a broken ankle he suffered in October.

The Scotland international is an attack-minded full-back and already has 10 assists in 22 appearances this season.

The Mirror claimed earlier this month that Manchester United, Arsenal, Chelsea and Manchester City were all interested in Tierney, despite his current contract set to keep him at Celtic Park until 2021.

Football Insider verdict:

Celtic should reject any January offers from Sunderland for Tierney as they could really cash in on the player in the summer. The youngster seems destined to play for a top club in England and has already been touted with a potential move. He is one of Celtic’s top performers and a crucial player in Brendan Rodgers’ side. They should keep hold of him until the end of the season and then listen to offers in the next window. Tierney appears to have all the assists of a modern day full-back and should have a huge price tag on his head. It would also be in the best interests of the player to see out the campaign with the Bhoys and collect some silverware before deciding on his future.

In other Celtic transfer news, the club are battling West Ham for an international defender.

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