The livewire striker is the latest in a long line of academy graduates to progress into the Ipswich first-team.
He was brought on by Royle in the 66th minute at Ninian Park, replacing skipper Magilton. In the 85th minute he showed great trickery to evade two Cardiff players on the edge of their area, before he was brought down for the free-kick from which Frenchman Jimmy Juan scored.
Clarke, capped by Ireland at youth level, follows Owen Garvan and Danny Haynes this season in making the step from the successful Ipswich academy into the first-team. With Parkin sidelined for 11 weeks and Naylor likely to have to revert back to defence if Wilnis' red card isn't overturned, the young Irishman may yet have more oppourtunites to stake a place in the Town attack.