Clare 2-21 Offaly 0-15
Clare got their Division 1B campaign off to a winning start at Cusack Park in Ennis as Peter Duggan's goal just before half-time helped Davy Fitzgerald's side past a hard-working Offaly.
Duggan and Offaly's Conor Doughan were both sent off midway through the second-half and Offaly were reduced to 13 men 12 minutes from time when Paddy Rigney picked up his second yellow card.
At that stage Offaly trailed by eight points and had Shane Dooley managed to convert 61st minute penalty things might have been different for Eamonn Kelly's side, but an added-time goal from Aaron Shanagher wrapped up the win for Clare.
Despite a poor opening 20 minutes Clare were good value for their 1-13 to 0-7 lead at half-time. Clare hit 1-9 in the last 12 minutes of the half with Peter Duggan's goal a huge blow for Offaly in the first minute of added time.
With Shane Dooley in fine form from placed balls Offaly worked their way into a good early lead, and after points from Paddy Murphy and a free from Doughan on his own 65, they held a 0-6 to 0-4 lead after 21 minutes.
But Clare took over from there until the break as a solitary Dooley point was the only interruption to their utter dominance.
John Conlon pointed after the restart to get Clare up and running again, although he limped off soon after, while the red cards for Duggan and Doughan after 50 minutes came following an off the ball altercation.
Dooley kept Offaly in touch with a couple of frees, but crucially he was off the mark with a penalty nine minutes from time, shortly after Rigney received his marching orders.
A goal at that stage would have cut Clare's lead to five points, but instead they kicked on and Aaron Shanagher's goal in injury-time wrapped up the win.
Clare will look for consecutive wins when they travel to take on Wexford next weekend, while Offaly face a derby with Laois.
Scorers for Clare: Colin Ryan 0-9 (7f); J Conlon 0-3; A Shanagher, P Duggan 1-0; B Duggan (1f), D McInerney 0-2; C Cleary, D Reidy, C Galvin, S O'Donnell, C Dillon 0-1.
Scorers for Offaly: S Dooley 0-8 (6f, 1'65); P Camon 0-3; P Murphy 0-2; C Doughan (1f), S Kinsella 0-1.
Clare: P Kelly; P O'Connor, C Dillon, D McInerney; Conor Ryan, P Flanagan, C Cleary; D Reidy, C Galvin; Colin Ryan, J Conlon, P Duggan, S O'Donnell, D Honan, C McGrath.
Subs: A Cunningham for Honan (35+1 mins), A Shanagher for Conlon (39 mins), B Duggan for Colin Ryan (52 mins), D Fitzgerald for McGrath (57 mins), J Browne for Conor Ryan (64 mins).
Offaly: J Dempsey; N Wynne, C McDonald, P Rigney; P Camon, C Doughan, S Gardiner; P Guinan, S Kinsella; P Murphy, S Dooley, J Bergin; J Mulrooney, C Egan, J Sampson.
Subs: J O'Connor for Guinan (32 mins), S Quirke for Sampson (35+1 mins), S Cleary for Mulrooney (63 mins), B Murphy for Bergin (65 mins)