Roscommon will face London in the FBD League semi-final after Mayo were dumped out of the pre-season competition.
London sprung an early season upset in the 0-12 to 1-8 victory at the Connacht GAA Air Dome. Mayo having led six points to five at half-time.
London produced a big second-half display, but veteran Diarmuid O’Connor’s 50th minute goal seemed to set Mayo up for a win.
However Shay Rafter landed what proved the winning score for the Exiles a minute from injury-time. London will return to the air dome to face Roscommon on Saturday evening at 7pm.
Roscommon crushed a slow starting Sligo on Friday night.
The first semi-final will see Leitrim face Galway in the air dome on Friday night at 7pm.
Meanwhile, Longford will face Meath in the O’Byrne Cup semi-final also on Friday night at 7:30pm under lights in Ashbourne.
Tailteann cup champions Meath overcame Louth 2-13 to 1-7 to setup a semi-final meeting with Longford.