Stan Collymore has suggested that Newcastle United fans should not get carried away with Alexander Isak just yet.
Although the former Liverpool striker has been impressed by Isak, the pundit has noted in CaughtOffSide that he is not fully sold on the 23-year-old Sweden international striker just yet.
Collymore has said that Isak has yet to prove that he can do it on a regular basis in the UEFA Champions League.
The former Aston Villa striker has also raised doubts on whether the youngster could step up when the going gets tough for Newcastle.
Stan Collymore on Newcastle United striker Alexander Isak
Collymore wrote: “Secondly, on Isak, I wrote about him a couple of months ago and was quite harsh on the lad.
“I basically said that I wasn’t sure he is the right player to lead Newcastle’s line on his own, and although he’s not exactly proving me right, I will remain cautious over talking up his ability too much until I see him do it in the Champions League, assuming Newcastle finish inside the top four this season.
“But there is no doubt about it, he’s young, incredibly talented and quite clearly has an eye for goal.
“My only concern would be that if the side hit a tough period through injuries or bad results, will Isak be the type of player to drag them through, such as Harry Kane has done for Tottenham over the years?”

HITC Verdict: Promising talent
In our view, Newcastle United fans should be positive about Alexander Isak.
The striker has had injury problems this season, and that has affected his development.
However, Isak is playing regularly for Newcastle and is doing extremely well.
The former Real Sociedad youngster has made 11 starts and four substitute appearances in the Premier League for Newcastle so far this season.
Isak has scored 10 goals in those games.
The striker is a regular for Sweden and has played 39 matches for his country.
The 23-year-old also played over 100 league games for Real Sociedad.
We believe that Isak has huge potential, and that the striker will get better and better in the coming years.
Newcastle have a real gem in Isak.
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