John Fleck netted his first goal for Rangers as they claimed a 2-0 victory over Dundee United and moved to within a point of Celtic in the Clydesdale Bank Premier League.
The teenager won, and then converted, a second-half penalty before Kyle Lafferty sealed the win in injury time.
The previous meetings between the clubs had both ended in draws but United were forced to return to Tannadice empty-handed this time as Rangers piled the pressure on Celtic ahead of the champions' trip to Inverness.
Simon Mensing scored both goals as Hamilton recorded their first-ever top-flight victory over Hearts to climb to eighth in the table.
Jambos owner Vladimir Romanov joined the New Douglas Park crowd to take in his first Hearts game since November 2007, but his side offered little attacking threat as Accies won 2-0 to complete a perfect January, which has yielded five straight victories in all competitions.
Mensing opened the scoring 11 minutes in by converting a Brian Easton corner and then made it four goals in as many games with a penalty early in the second half after Robbie Neilson brought down James McCarthy.
Hearts travelled without captain Christophe Berra, who is discussing terms with Wolves after the Tynecastle club accepted a reported £2.3million offer for the centre-half.
Dennis Wyness came off the bench to rescue a 1-1 draw for St Mirren after Kevin Kyle had threatened to spoil the Paisley club's first game at their new stadium.
Kyle headed home on his Kilmarnock debut and it looked like his would be the only bright new start after Alan Combe saved Jim Hamilton's penalty.
But Wyness grabbed a late equaliser after a mistake by Combe, who had controversially escaped a red card for hacking down Craig Dargo.
Michael Higdon's second-half goal gave Falkirk a vital 1-0 win over Aberdeen as they eased away from relegation trouble.
Former Crewe striker Higdon latched onto a pass from strike partner Steve Lovell 10 minutes after the break to net the only goal of the game and stretch the Bairns' advantage over bottom side Inverness to five points.
The defeat brought to an end a run of only one loss in nine games for Aberdeen, whose best chances fell to skipper Scott Severin on an afternoon of frustration in front of goal.
David Clarkson rescued a deserved 1-1 draw for Motherwell to deny Hibernian victory in a hotly-contested clash at Easter Road.
Clarkson converted a penalty with 15 minutes remaining following substitute Steven Thicot's foul on Jamie Murphy.
Hibs had taken the lead in the eighth minute when Derek Riordan found the net with a composed finish from 10 yards from Ross Chisholm's cutback.