The Everton winger got in behind Arsenals defence several times at the Emirates on Sunday, and shortly before half-time he was played in only to be denied by an excellent stop from the active Cech.
But the ball rebounded and smashed Walcott in the face, going out for a goal kick, and his eye quickly started to swell up as a result.
Walcott looked more like Alexander Povetkin after his bruising encounter with Anthony Joshua at Wembley on Saturday night as he left the field at half-time, his eye already showing severe bruising.
He required treatment on the pitch but was able to continue, though it is the second bizarre eye injury sustained by a Premier League player recently.
Last weekend, Liverpool beat Tottenham but goalscorer Roberto Firminos match was ended early when Jan Vertonghens finger ended up half way down his eye socket – fortunately he recovered in time to score the winner against PSG off the bench in midweek.
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