According to Calcio Mercato, Serie A giants Milan have earmarked Kristoffer Ajer as a potential transfer target for the summer.

What's the word?

The Norway international has been an ever-present for Celtic this season, making an impressive 49 appearances across all competitions - in fact, he has only failed to complete the full 90 minutes in the top-flight on four occasions.

And as per Italian publication Calcio Mercato, Milan are targeting defenders who are physically strong and with a sense of leadership, and feel Ajer "embodies these characteristics".

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The report further adds that the 21-year-old is "highly appreciated by the Rossoneri scouts, but Celtic has specified that he will not make any discounts".

Think twice

The Hoops have lost some crucial players from their back-line in recent years, not least players like Virgil van Dijk and even Kieran Tierney last summer.

At 21, Ajer still has plenty of time to really grow into his role at Celtic Park, and the fact he has been a mainstay of their team this season shows just how highly Lennon values him.

Back in February, the Celtic boss even lauded him for being a "model of consistency" all season, whilst just last summer he waxed lyrical about Ajer's abilities.

He said: "Kris is a fantastic player and has pretty much played every minute for me. He has been outstanding, and we have high hopes for him. Kris wants to improve, he is a regular international now, and you have to remember how young he is. He is athletic, good on the ball, good in the air and is an intelligent boy. Kris has all the strings to his bow, he is a real specimen at 21."

It's fair to say that Celtic still haven't yet seen the best of the 6 foot 5 Ajer, and if they have hopes of doing matching their domestic success in Europe, then keeping a hold of highly-rated players will be important. It's exactly why Peter Lawwell should be very wary of cashing in on a player who still has a lot more to give.

Meanwhile, Celtic fans blast this tweet from Alex Rae.