Fabian Delph's second start of the season lasted less than half an hour after he sustained a hamstring injury against Burnley.
The 31-year-old was picked to start as a left-wing back at Turf Moor today but pulled up in the first-half as the Blues trailed 1-0.
Ancelotti, who is without the injured Lucas Digne, did not include Niels Nkounkou in the matchday squad and was forced into a reshuffle following Delph's injury, putting Ben Godfrey in at left-back and Alex Iwobi at right-back as part of a 4-2-3-1 formation.
Andre Gomes came off the bench to replace Delph who walked gingerly down the tunnel.
Delph now joins Digne (ankle), Seamus Coleman (hamstring) and Jean-Philippe Gbamin (Achilles) on the sidelines.
Delph's time at Everton has been dogged by injury with the £8.5m signing having only made 15 league starts since joining in the summer of 2019.
