Synchronised will miss Sunday's Hennessy Gold Cup at Leopardstown after failing to satisfy connections in the run-up to the Grade One.

The nine-year-old, trained by Jonjo O'Neill, joins the list of high-profile horses to miss the Irish showpiece, but the Lexus Chase winner remains on course for the Betfred Cheltenham Gold Cup.

"Jonjo's not happy with him today and he's not going to send him over for the race," said Frank Berry, racing manager to owner JP McManus.

"He won't run again before Cheltenham and hopefully Jonjo will get him right for the Gold Cup."

With Synchronised joining Jessies Dream and Quito De La Roque on the sidelines, there is at least positive news coming out of Jessica Harrington's yard regarding Bostons Angel.

Last year's RSA Chase winner has disappointed so far this season but is being fitted with head gear on Sunday in an attempt to revitalise him and it seems to be working at home.

Harrington tweeted: "Bostons Angel schooled excellent with cheek pieces on this morning. Full steam ahead for the Hennessy on Sunday."