Midfielder Phillips serves the final game of a two-match ban following his dismissal in the draw at Fulham and right-back Ayling sits out the first of a two-game suspension after reaching 10 yellow cards.
Head coach Garry Monk has no new injury problems as his side bid to extend their unbeaten league run to seven matches.
Left-back Charlie Taylor, fit again following an Achilles injury, hopes to feature after he was an unused substitute in last week's goalless draw against QPR.
Brighton captain Bruno is fit after a groin injury.
The veteran Spanish right-back, who signed a new one-year contract this week, was forced off during last Friday's 3-0 win over Derby.
But the Seagulls are still without fellow defenders Shane Duffy (ankle), Sebastien Pocognoli (groin) and Gaetan Bong (knee).
Norway centre-back Vegard Forren, who joined last week, will play for the under-23s before coming into contention.