Celtic will need to strengthen their options on the flanks this summer. The club did make two additions in those areas last season, but neither can be considered an outright success.

Celtic were rather fortunate that Yang Hyun-jun raised his game and established himself as a starter. Otherwise, they might have been completely ineffective on the wings all season.

Sebastian Tounekti played a ton but after a bright start, it never looked like he was performing at a consistent level. Most fans viewed him as the weak link in the team by the end of the campaign.

But at least Tounekti contributed. The same cannot be said about Michel-Ange Balikwisha.

Celtic chased the signing of Balikwisha for more than a year. And one can only wonder what they saw in him. He most certainly has not been able to produce anything meaningful in a green-and-white jersey.

Balikwisha played a handful of games after coming in and was then completely frozen out of first-team plans for the rest of the season. In the grand scheme of things, he might be one of the worst signings in the history of the club.

So, it should not come as a surprise that the club are looking to strengthen in that position right now. And a Borussia Dortmund winger is on their radar.

According to Patrick Berger, Celtic are one of the clubs interested in signing Cole Campbell. The winger will return to Borussia Dortmund after his half-season loan at Hoffenheim. TSG did not trigger the purchase option.

Campbell is open to leaving Borussia Dortmund this summer. Initial talks with Celtic have started.

Campbell spent the second half of the season out on loan at Hoffenheim but did not play much. 

While the American winger, born in Houston, was a standout in the youth levels for Borussia Dortmund, that clearly has not translated to the senior game so far.

So, while he might have the flashy tag of being a 'Borussia Dortmund winger', that does not necessarily mean that Celtic would be getting an instant game-changer, if they sign him.

READ MORE: Celtic Handed More Bad News About Coaching Situation

That being said, one cannot be too critical of Campbell either. Let's not forget, he is still just 20 years of age. It is not easy to establish yourself at a club like Dortmund this early on, despite their record with youngsters.

A move to Celtic could serve him very well. Now, it remains to be seen what the future holds for Campbell.

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