It is a sign of the times that Pierre van Hooijdonk took to Twitter to applaud his countryman's move to Celtic last week.

Virgil van Dijk became Neil Lennon's second signing of the summer when he agreed a four-year deal with the club – and former Hoops striker van Hooijdonk was thrilled to see the player head to Glasgow.

Tickled by van Hooijdonk's Tweet, van Dijk left a message for the former Dutch internationalist over the weekend, thanking him for his comments and suggesting that he would be in touch for a few pointers regarding life in Glasgow.

Having watched the 21-year-old impress in his native league this season, van Hooijdonk believes Celtic have unearthed a player of genuine quality – and has insisted that he will be another whom the Parkhead club will see a sizeable return for their outlay.

"I have no doubt that Virgil is a player who will be worth a substantial amount of money in the not too distant future," said van Hooijdonk.

"Often when you see a player go to a club, especially if it is a club you yourself have played for, you have a gut feeling whether or not it is the right move for either the player or the team and you suspect it might not work out.

"I don't have any concerns whatsoever with Virgil – he will be a success with Celtic, of that there is no doubt.

"He is a player that a few of us have seen make real strides forward last season and a lot of people expected that he would move to one of the big clubs in Holland.

"I honestly believe Celtic have pulled off quite a signing by getting him."

Van Hooijdonk expects the defender will go on to make a name for himself at international level, too – he has so far been capped at Under-19 and Under-21 level – and doesn't believe that playing in Scotland will detract from his international ambitions.

The likes of Gary Hooper and Fraser Forster have been frustrated at their lack of recognition from England because of where they ply their trade, but van Hooijdonk does not believe there will be a barrier put in place for van Dijk.

However, he has stressed the need for European involvement. "We don't see many Scottish games on television in Holland but we do get the Champions League games," said the former striker.

"That is where Virgil will get the chance to show that he can fit in with the elite in the game. If you can handle yourself in that competition then you are good enough to be playing for your country.

"I know that people don't always look kindly on the Scottish league, but I think Virgil will improve there.

"He is Dutch, he will never have experienced anything like Celtic Park when it is full or the pressure that comes with having to win and having to win a certain way. It will all be new to him and it will take him by surprise – just as it did me.

"There is an intensity to playing with Celtic that you need to experience to understand.

"He will have seen the club and the set-up, he'll have seen the stadium and met his team-mates but he won't appreciate just yet how big a club it is – or how you have to perform no matter what. That pressure will be good for him.

"And if Celtic are successful in getting back into the Champions League group stages then it will be the next big learning curve for him. Like many people in Holland, I expect big things from him over the next few years."

And van Hooijdonk believes van Dijk will win over the Hoops fans not only with a solid defensive approach – at 6ft 4in he is expected to be on the end of most things – but also with the fact he is comfortable with the ball at his feet.

"I wouldn't put any pressure on him by comparing him to other players.

"But what I will say is that he is physical, he is strong. But he doesn't only stop goals by making life difficult for defenders, he is also very good at playing some good stuff out of defence too.

"I still see Celtic often. I was back in Glasgow for the Scottish Cup final at the end of the season and I really don't see that he will have a problem fitting in.

"It will certainly take him by surprise just how big the club is. But he will become a real favourite because he is gives his all and he is a player of genuine quality."