Chelsea announced on Wednesday afternoon that they had agreed a deal with Real Madrid to bring the 24-year-old Spain international to west London after having been heavily linked with a move to sign the striker for much of the summer.
Morata had been heavily linked with Manchester United for much of the summer but has ended up moving to Chelsea.
However, Saunders has warned that signing Morata represents a “gamble” and pointed to Andriy Shevchenko’s failed time at Chelsea as a possible warning for the Blues over Morata.
Speaking on talkSPORT, Sanders said: “Turn the clock back a while, Shevchenko signs for Chelsea.
“Everybody in the world would have signed him and it didn’t happen for him.
“Whether it was the different country, didn’t settle in, played with a different partner than he used to play with.
“It’s always a gamble. I think the only safe bets you’ve got are people like (Alan) Shearer and Michael Owen, people who have been brought up in this country and done it for 10 years on the bounce.
“(Jermain) Defoe, I keep going on about him, he’s the nearest thing to a safe bet.
“If Defoe played for any of the top six next year and played every week, he’d get 15-20 goals. What’s that worth? Free transfer he was.”
Morata is set to become Chelsea’s fourth signing of the summer after the arrivals of Willy Caballero, Antonio Rudiger and Tiemoue Bakayoko.
The west London side are aiming to defend their Premier League title next season as they also gear up for a return to the Champions League in Antonio Conte’s second campaign in charge.
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