Lineker loses his voice after BBC return
The former England striker was restored to his presenting role for live coverage of Manchester City's 6-0 thrashing of Burnley on Saturday, a week after being taken off air in an impartiality row.
Lineker was criticised for comparing the launch of the UK government's new asylum policy to the rhetoric of Nazi-era Germany.
However, his removal sparked chaos across the BBC's sporting coverage as presenters, pundits and commentators showed their backing for Lineker by refusing to work.
A compromise was reached on Monday as the two sides said they had agreed that Lineker would return to screens while the corporation launches an independent review into its social media guidelines.
Lineker, who is the BBC's highest paid presenter, said "it's great to be here" as he fronted live coverage from the Etihad.
But the BBC said on Sunday he would not present Brighton's quarter-final clash with fourth-tier Grimsby due to illness.
"Due to illness, we've got a line-up change for today's live FA Cup coverage of Brighton v Grimsby on BBC One," BBC Sport tweeted.
"As viewers will have noticed yesterday, Gary Lineker was struggling with his voice and unfortunately it has deteriorated overnight. Alex Scott will be hosting instead."
Former England women's international Scott was one of the presenters who refused to work last weekend in support of Lineker.