Chelsea have been left to rue the decision to sell Marc Guehi following the 21-year-old's metamorphosis into one of England's leading centre-halves. The Cobham graduate, who swapped Stamford Bridge for Selhurst Park in the summer for a deal worth just £20 million, was one of many departures that funded a £110m windfall that secured the services of Romelu Lukaku.
Guehi has impressed under Patrick Vieira, completing 90 minutes in all but one of the Eagles' Premier League clashes this season as the south Londoners look to swoop in on new territory. The newly-capped England international has guided Palace into the top half of the Premier League and to a FA Cup semi-final.
Ironically, the young defender has transcended into the perfect candidate for Thomas Tuchel's new-look defence next season. The deal agreed between the London sides includes an opportunity for Chelsea to buy Guehi back for the same fee agreed with another club, according to the Guardian, should the German look to bring him back.
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Despite the west London side's clause that offers a silver lining, Chelsea have paid the price for not investing faith into a returning loanee. Last season, Guehi earned his stripes out on loan at Swansea City in the Championship.
He impressed and guided the Swans to a Premier League play-off place but fell short at the final hurdle against Brentford. Similarities can be drawn between Guehi and starlet Levi Colwill, who's currently learning his trade in the Championship.
According to The Athletic, Tuchel is looking to assess Colwill's development at the end of the season as a route into the Chelsea first-team begins to open up. Antonio Rudiger and Andreas Christensen both see their current deals in west London expire at the end of the season.
With a vacancy opening, the Blues boss must learn from the club's mistake to offload Guehi without much hesitation and hand Colwill a role that offers valuable first-team minutes next season. And the German looks to have already learned his lesson after outlining his faith in Cobham graduates.
Speaking in the pre-match press conference ahead of Chelsea's FA Cup semi-final bout with Palace, Tuchel said: "We will always use as many academy players where possible. I said before, and I think it makes the club very special and makes every team in the world very special if you have a mix between world-class players, big personalities from abroad and outside the club, and mixed with academy boys.
"It is also very important for academy boys to match the level, to realise the level of commitment, professionalism, and players that come from other clubs and bring the best of their cultures. It is very, very important for our youngsters and academy players to accept that mix and accept that challenge. Then it can be very special because this is what makes teams special, that there are plates from the academy."
The Blues boss added by addressing Guehi's departure. Tuchel noted the defender's development and detailed his outlook on handing opportunities to young players.
"For Marc, his is a fantastic development," he said. "It's very hard or maybe even is impossible now to say if we kept him, he would have been better, worse, or been the same. Maybe he needed to leave.
"Maybe he needed the change of environment, a different club, a different or bigger role, more minutes to develop his full potential. It just tells you over and over again that if you trust younger players and have a role for them, they can on a very regular level, match expectations and even over-perform.
"It's nice to see so many Chelsea players out there in every league. We are well aware of it. It is nice to play against them and see them develop."
