There were 13 scores in a free-flowing opening 13 minutes in Banagher before the game degenerated into a battle, with both teams finishing with 13 players.
First to go was Derry's Cormac McKenna on a straight red after 24 minutes. London veteran Martin Finn (second yellow) followed him 15 minutes into the second half and then Derry's Ruiri Convery and London's Niall Forde also saw red.
A Martin Finn goal after 24 minutes saw London come from behind to be level 1-6 to 0-9 at the interval.
Kevin Hinphey and Oisin McCloskey rallied Derry, and Hinphey booted a cross to the net for a one-point lead.
Jimmy Mulcahy put the teams level but, with time almost up, Paddy Kelly got the winner.
SCORERS -- Derry: K Hinphey 1-2, O McCloskey 0-5, R Convery 0-3f, P Henry 0-2, P Kelly, P McCloskey 0-1 each. London: M Finn 1-4 (0-4f), P Sloane 0-4 (2f), N Forde, M Walsh, R O'Connell, J Mulcahy, S Ryan 0-1 each.
Derry -- D McDermott 9; A Rafferty 8, M Craig 8, L Hawkins 6; D McCloskey 7, C McKenna 5, S Cassidy 6, K Hinphey 9; O McCloskey 8, A Grant 7; R Coinvery 6, P Henry 6; O Doherty 5, C McKeever 6, P Kelly 7. Subs: P McCloskey 7 for O Doherty M Kirkpatrick 5 for McKeever.
London -- A Ryan 8; J Hartley 7, B Costello 7, C Burke 8; C Forde 7, N Healy 7, M Walsh 7; M Fitzimmons 6, N Forde 6, K Kennedy 6; S Ryan 7, R O'Connell 6; P Sloane 8, H Vaughan 6, M Finn 7. Subs: T Twomey 6 for Fitzimmons, J Mulcahy 7 for Twomey.
Ref -- G Duffy (Antrim).