'Costa Situation Worrying'  (Sky Sports)

Chelsea fans are understandably concerned by uncertainty surrounding Diego Costa's future, according to former Blues winger Paul Canoville.

Costa was excused from the first week of pre-season training at Cobham and has now been left out of Chelsea's pre-season tour to China and Singapore.

Despite being Chelsea's top scorer last term, Costa was told by manager Antonio Conte that he was not part of his plans for next season and has since been linked with a return to former club Atletico Madrid.

The Premier League champions were dealt a blow last week when they were beaten to the signature of Romelu Lukaku by Manchester United, who are still understood to be keen to sign Chelsea midfielder Nemanja Matic.

Canoville believes another striker must arrive at Chelsea but admits he has reservations about a move for Real Madrid frontman Alvaro Morata, who has been linked with a big-money move to Stamford Bridge.

"It is a worrying situation because Chelsea need a striker in place," Canoville told Sky Sports.

"If Costa leaves it will leave Chelsea short in terms of firepower up front. Hazard got injured as well [on international duty with Belgium] and won't be ready for the start of the season.

"The club have brought in a couple of players for other positions but it's a situation that needs sorting out because Loic Remy and Michy Batshuayi as the two main strikers is not enough.

"Everyone knows that in the Premier League you need a standout striker. You need someone who's capable of holding the ball up and can finish.

"Chelsea have been linked to [Dortmund's Pierre-Emerick] Aubameyang and Morata but foreign teams are asking English clubs for a lot of money for these players and there is no certainty that they can do it in the Premier League.

"Morata has also not been getting regular games at Real so he's bound to be a little rusty. Chelsea need a player that is suited to the system and can build up his fitness during pre-season and can fit in right away."

Chelsea signed Willy Caballero and Antonio Rudiger earlier this summer and have just completed the £40m acquisition of midfielder Tiemoue Bakayoko from Monaco.

Both Manchester clubs have spent far more than the Blues this summer, but Canoville is not unduly worried, insisting Conte has a plan.

"There's no real need to panic but lots of fans nowadays worry when they see other clubs spending so much," he said.

"But I'm convinced Chelsea know what they are doing and Conte definitely knows what he is doing. I'm sure Chelsea will bring in the right players to help them compete on all fronts."