Diego Costa is so desperate to prove his fitness to Jose Mourinho that the striker shunned the Chelsea manager’s offer of two days’ rest.

The Premier League top scorer has been struggling to manage his tender hamstrings and there was no let up for the £32million man during the international break.

He played 82 minutes in the win over Luxembourg on Sunday and 90 minutes in the surprise defeat to Slovakia on the Thursday before.

Surpise: Jose Mourinho didn't expect to see Costa back so soon

Ramires, Didier Drogba, Andre Schurrle and John Obi Mikel, along with a jaded Costa, are doubtful for Saturday’s trip to Crystal Palace with niggling problems.

Costa and his Spanish team-mates Cesc Fabregas and Cesar Azpilicueta were told they were not needed back at Cobham until midweek.

However, the former Atletico Madrid man was at the training ground bright and early first thing on Monday morning, much to the amazement of his boss.

In training: Cesc Fabregas and Diego Costa

“The Spanish team played in Luxembourg on Sunday, I gave them Diego, Fabregas and Azpilicueta. I gave them two days off," Mourinho said.

“I gave them Monday and Tuesday off, so they have to report to train on Wednesday at 3pm. And Diego was here on Monday at 9am.

“So you can imagine how strong he was to be here on Monday.”

Still sidelined: Chelsea's Didier Drogba

Five players on the treatment table is hardly the preparation Mourinho wanted going into the Palace game and the Blues boss is waiting until the last minute before settling on his team.

“I want to wait until tomorrow. But we have some problems,” Mourinho added.

“Ramires, Drogba, Diego, Schurrle, Mikel - it’s a long, long list."