Middlesbrough boss Neil Warnock has been fined £7,000 by the Football Association for comments he made following his side's defeat by Swansea.
Warnock then criticised the officials after the full-time whistle in the Championship game on 6 March.
"The manager admitted that comments he made during post-match interviews constituted improper conduct," the FA said in a statement.
"They questioned the integrity of the match official, implied bias, were personally offensive and brought the game into disrepute contrary to FA Rule E3.1."
Ayew's spot-kick came deep into stoppage-time after referee Gavin Ward had initially given a corner.