The injury-plagued Summerhill man suffered cruciate knee ligament damage while training on Sunday and will miss the entire Championship.
He’d just returned following a shin break and was in line to start against Carlow in Sunday’s provincial quarter-final.
Powerful Gillespie had established himself as Meath’s first-choice midfielder and had a strong game in last year’s Leinster final.
He is the fourth Meath player to be ruled out for the rest of the year, with Davy Dalton, Cillian O’Sullivan and Eamonn Wallace also sidelined.
Manager Mick O’Dowd does at least have options for the Carlow encounter as Shane O’Rourke and Brian Meade are both back in the frame after long-term injuries. O’Rourke has finally overcome long-term hip trouble while Meade has made a full recovery from a cruciate injury.
O’Dowd admitted he was forced to use O’Rourke more than he would have liked in the league. But the gamble has paid off, particularly in light of the Gillespie development.
O’Dowd said: “To be fair to Shane, if Conor and Brian had been available during the league, he mightn’t have played as much. We might have tried to mind him a little bit more than we did. In hindsight, it has proved to be very good for him to play as much as he did. Shane probably has another step to take his game up but that’s what the month of May was for, to help him along and sharpen him up.”
Bryan Menton had emerged as a midfield option for Meath but he’s out of the Carlow game with a dislocated thumb. Eoghan Harrington is also out after suffering a hairline jaw fracture.
Experienced duo Stephen Bray and Kevin Reilly will both be back however after missing recent club and county games.