There is a considerable sell-on clause in Sam Johnstone's West Bromwich Albion contract.

What's the talk?

That's according to The Sun journalist Alan Nixon, who claimed in a post on Twitter that the Baggies' steep asking price for the 28-year-old shot-stopper is likely down to the fact that Manchester United have a sizeable sell-on clause in the £7.2m-rated man's deal.

Nixon said: "There's a sell on. But that’s probably why West Brom are pricing him high."

Ole Gunnar Solskjaer's side have recently been linked with a move to bring their former player back to Old Trafford this summer, while West Ham United are also believed to be keen on the 'keeper, although David Moyes is thought to have been put off by the £20m asking price.

Fans will be gutted

While the West Brom faithful will undoubtedly be disappointed by the prospect of losing their first-choice shot-stopper this summer - especially when considering how important he has been within his side in recent seasons - this latest update will surely leave them even more gutted.

Despite the fact that the Baggies suffered relegation to the Championship, Johnstone nonetheless impressed for Sam Allardyce's side over his 37 Premier League appearances this season, helping his side keep six clean sheets, as well as making an average of 4.5 saves and 0.4 successful runs out per game, in addition to making a total of 166 saves in the league.

These metrics saw the £28k-per-week 'keeper - whom Allardyce dubbed a "magnificent" player - earn a highly impressive seasonal SofaScore match rating of 7.03, ranking the 28-year-old as the club's second-best performer in the top flight.

As such, it is no wonder why a number of clubs are believed to be interested in the former Manchester United man this summer, and why West Brom are asking for a considerably large amount for the goalkeeper.

However, this will not change the fact that West Brom fans will be devastated about Johnstone's sell-on clause, as, if Man United were to offer the £20m asking price for the shot-stopper and the clause was, for example, 20%, the Baggies would be losing out on a whopping £4m for one of their star players - meaning less money for the club to reinvest on incoming signings.

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