(CNN) -- Scott McDonald sent Celtic seven points clear in the Scottish Premier League title race with the only goal of Saturday's clash against Old Firm rivals Rangers.
Scott McDonald, flanked by Scott Brown and Koki Mizuno, celebrates scoring against big rivals Rangers.
Defending champions Celtic were determined to set the record straight after an early-season 4-2 home defeat and McDonald delivered the decisive blow after 57 minutes.
Georgios Samaras's flick-on was met by McDonald and he beat goalkeeper Allan McGregor with a superbly struck volley from just inside the area.
Rangers had enjoyed the bulk of the possession but were unable to match McDonald's finishing touch
The home side had the ball in the net after 11 minutes when Kirk Broadfoot bundled home in a packed goalmouth, but referee Craig Thomson had spotted a foul on keeper Artur Boruc and ruled out the effort.
Instead it was Celtic who later almost added a second when Paul Hartley's free-kick found Samaras at the back post and McGregor just managed to hold the downward header.
"Losing at home hurt us quite a lot, so we wanted to come here and take a bit of revenge." McDonald told Setanta Sports. "Our first win (at Ibrox) in three years - it's a fantastic feeling."
It was the Ibrox club's first domestic home defeat in 2008 and Celtic manager Gordon Strachan recognized: "They have had a good year Rangers, fantastic year, especially at home. For us to come here and to get a victory is very satisfying."
Lee Miller's first-half strike gave Aberdeen their fifth consecutive home win 1-0 against 10-man Hearts at Pittodrie.
The Dons striker hit his seventh goal of the season when he volleyed home Scott Severin's freekick.
Marius Zaliukas was sent off in a fiery second half for elbowing Andrew Considine when a melee broke out in the Aberdeen penalty box.
A 22nd-minute strike from Scott Robertson was enough to give Dundee United all three points against Falkirk.
The visitors finished the game with 10 men as skipper Darren Barr was red-carded following two second-half bookings.
Chris Porter headed a hat-trick as Motherwell marked the approaching anniversary of Phil O'Donnell's death with a much-needed Premier League victory.
Porter scored twice in the first half and completed his treble in the 78th minute, the exact time last year when the late skipper collapsed against Dundee United.