However, having established good field position Connacht kept the pressure on and were rewarded in the 26th minute when slick handling saw Conor Finn score wide on the left, Leader's touchline conversion edging the visitors ahead.
Munster's response was immediate and when they won a kickable penalty they opted for touch ten metres out. Phillip Donnellan took cleanly at the tail but there was no reward as Cusack's drop goal attempt drifted right and wide.
That proved an expensive miss because minutes before the break Connacht Munster of possession on the half way fo Leader to race in under the posts unopposed.
Munster had the final say when Cusack kicked a penalty to leave his side trailing by five points at the interval
Munster A: R O'Mahony; C Hircock, JJ Hanrahan, T Gleeson, L O'Dea; D Cusack, G Hurley; D Kilcoyne, D Fogarty, J Ryan; D Foley(B Hayes 37th min), P Donnellan; S Buckley, B O'Hara, P Butler captain. Replacements: S Henry, J Cronin, C Condon, J Shine, C Sheridan, G Quinn-McDonagh, D Moroney.
Connacht A: C Boland; J Loxton, R Henshaw, T Leader, C Finn; J Carthy, D Moore; F Bealham, D Murphy capt, S Maguire; M Kearney, D Qualter; D Heffernan, A Conneely, E McKeon.