David Rutherford’s second of the night, just 50 seconds into the extra session, sealed the points for the Giants.
The win completed a successful weekend for the Giants, as they’d already triumphed 4-2 at home to Fife Flyers in the Elite Challenge Cup.
Nottingham Panthers picked up four points from their weekend road trip to Scotland.
David Clarke scored twice in their 3-1 victory at Dundee Stars and Panthers followed up with a 4-1 success at Braehead Clan.
The Flyers proved too strong for Corey Neilson’s team in the third game, running out 4-1 winners.
Jake Morissette (2) led the scoring for Cardiff Devils as they secured a 5-1 home victory against Clan.
Manchester Storm sealed their first cup victory of the season with a 4-2 home win against the Devils.
Edinburgh Capitals had a miserable start to their cup campaign, losing 8-3 at home to the Stars.
Sheffield Steelers bowed out of the Champions League, but produced an excellent performance in their final group game to defeat Red Bull Salzburg.
Jesse Schutlz hit a hat-trick as Steelers won 5-2 against the Austrian outfit who’d already qualified for the last 32 alongside Sweden’s HV71.
Cardiff Devils 5-1 Braehead Clan
Coventry Blaze 2-3 Belfast Giants (OT)
Edinburgh Capitals 3-8 Dundee Stars (Cup)
Fife Flyers 4-1 Nottingham Panthers
Sheffield Steelers 5-2 Red Bull Salzburg (Champions Hockey League)
(Image permission: Press Eye)