Costa could face Swansea

Costa was plagued with a similar issue before recovering to score twice in a 6-3 victory at Everton before the international break.

However, the 25-year-old's fitness was once more cast into doubt when he suffered a recurrence of the complaint and missed Spain's Euro 2016 qualifying fixture with Macedonia last Monday.

Despite that setback Chelsea manager, Jose Mourinho is hopeful the in-form striker can feature against Garry Monk's men at Stamford Bridge on Saturday, with the former Atletico Madrid man set to undergo a late test.

"As you know Diego came back injured but that was last Saturday, so he had one week to work hard with the medical department and he has a chance to play tomorrow," Mourinho said. 

"We have a training session now to confirm his condition and to make a final decision."

Costa has started life at Stamford Bridge in fine fashion, scoring four goals in Chelsea's three Premier League games so far.

Mourinho is unsurprised by his impact and believes the front man fits the style of the team.

"When we bought him we were very optimistic," he added. "His profile as a player and as a person [fits Chelsea], he finds it easy to adapt. 

"A player is also part of a team and we knew the team was growing in a certain direction and was waiting for a player like him to be there. 

"His start was good, three matches, three victories, four goals, good performances, it was a good start."

Mourinho was also asked whether Thibaut Courtois' new five-year deal could cause fellow goalkeeper Petr Cech to become unsettled.

But the Portuguese insists Cech was well aware that Courtois would be signing an extension when he returned from a three-year loan at Atletico in the close-season.

"I don't think there is any problem," Mourinho continued. "Petr is a very intelligent guy, he knows when Courtois came back it [would be] to sign a new deal and to stay a long time. 

"No one would expect Courtois to come here with no new contract and in two years' time to be a free agent and Chelsea to be in trouble. 

"What happened is something that was already on the table and everyone could expect. 

"We have Courtois with a five-year deal and gives us that stability we want with such a good player."