Costa has not featured for the Blues since suffering a hamstring injury during the 2-1 win over Stoke City at Stamford Bridge back at the start of April but is likely to be in contention for Monday’s clash at The Hawthorns.
Mourinho also revealed that Ramires, Kurt Zouma and Oscar will not feature again for the Blues this season due to injury, while Petr Cech could be back in time for Chelsea’s last game of the season.
Mourinho told a news conference on Friday afternoon: “I think Diego Costa is selected for this game.
“I cannot confirm now because the game is on Monday but with two days to train I think he should be ready for this game.
“For Ramires and Oscar the season is over. For Zouma the season is over. Petr Cech has a chance to be back for the last match.”
Chelsea head into their penultimate game of the season having won seven of their last 10 Premier League matches.
Mourinho’s men, who are 11 points clear at the top of the table, were held to a 1-1 draw by Liverpool at Stamford Bridge in their most recent Premier League outing last weekend.
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