An Isak departure would be a huge loss for the Magpies, who have been active on the transfer market themselves but would have a massive hole to fill should the Sweden international leave the club.

Chris Waddle, who played for Newcastle in the 1980s, says losing Isak would be a big blow for the club as they look to build a squad that can improve upon their fifth-place finish from last season.

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Speaking to Flashscore, who offer a list of best betting sites, Waddle said, “I think Newcastle obviously have gone about their business nicely at the moment. They've had a couple of additions that are good players. 

“Obviously players leave and they're moving forward, but to see Liverpool in for Alexander Isak is obviously very disappointing because we know that he's a top player.

“He's a very important player to the way Newcastle play and if they're going to get success they need him up front.

“They have been linked with other players like Hugo Ekitike [from Eintracht Frankfurt], but let's be perfectly honest, I don't think there’s a better striker at the minute in the Premier League than Isak. 

“You can see why Liverpool obviously are interested. I think they'd like to get Darwin Nunez moved on and bring a new number nine in."

Waddle believes Isak's private nature has led to consternation among Newcastle fans, some of whom assume the worst amid the lack of available information.

The former England international thinks a word or two from Isak would go a long way towards easing fans' concerns.

“Isak is very quiet, he never really comes out and does any interviews, never really talks about his life, his future," Waddle said. "So for Newcastle, I'm sure the fans in particular would love him to come forward and answer a few questions.

“I'm sure Isak has got a lot of love for Newcastle United, but as I said, football is a short term business. Opportunities don't come around like the offer he’s got at the minute very often. 

“So yes, I'm sure he's had his head turned slightly. He doesn't seem to do any interviews and it would be nice just before the season starts to say, 'I'm staying at Newcastle and I'm just going to play out this season, enjoy it and we'll see where it takes me from there.'

“I think just a simple statement would then stop all the speculation about him.”

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