has confirmed that he is battling an illness at the ATP Finals.
The world No. 3 raised health concerns when he was ahead of the tournament.
He was then , repeatedly blowing his nose and grabbing his stomach throughout the contest.
Alcaraz has now raised alarm bells for the rest of the tournament, admitting it was tough to see himself getting out of the group stage and into the semi-final.
The Spaniard still has two more matches to play on Wednesday and Friday. If he wins them, he could still have a good chance of reaching the last four.
But that seems out of reach for last year's semi-finalist, who confirmed he got sick ahead of the tournament and struggled during his 6-1 7-5 defeat to Ruud.
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