Nicky Clark turned in a man-of-the-match display against his former team Dunfermline to help Dundee United to a vital 2-0 win and cement their place at the top of the table.
The former Pars hitman teed up Lawrence Shankland for the opener on nine minutes before curling in a tremendous free-kick on 25 minutes to win the Tangerines all three points and keep top spot in the Championship outright.
United manager Robbie Neilson made three changes from the 4-0 defeat at Queen of the South with Jamie Robson, Peter Pawlett and Clark coming in for Paul Watson, Sam Stanton and Louis Appere.
Unbeaten in their last four, Dunfermline only showed one difference to their starting XI with Andy Ryan coming in for Kevin Nisbet for the Tannadice clash.
And it was United who started strongest as they took the lead on nine minutes.
Liam Smith’s initial delivery from the right caused Cammy Gill in the Pars goal to flap at the ball and when Clark launched it back into the box, Shankland made no mistake from six yards out to net his 15th United goal of the season.
Two minutes later Dunfermline threatened to net a quick equaliser but Benjamin Siegrist in the home goal was a match for Ryan’s header. On 24 minutes, the Pars had another chance to draw level but Kyle Turner blasted over from 12 yards.
However, it was former Par Clark who came back to haunt his old side three minutes later as the Terrors doubled their lead.
After Ian Harkes was fouled on the edge of the box, Clark smashed home his first of the season with a curling right-footed free-kick from 25 yards out leaving Gill rooted to the spot.
Paul McMullan nearly made it 3-0 on 42 minutes, sliding onto Smith’s low delivery at the front post, but Dunfermline managed to clear the danger.
Three minutes after the restart Calum Butcher rifled a full volley just over the bar from 25 yards after the ball broke kindly for the Englishman.
Having only just returned from injury there was concern over Robson on 54 minutes when he went down in his own box but after receiving treatment he was OK to continue.
On 58 minutes the Fifers had their best chance of the match as Josh Edwards slid in former Terror Ryan Dow but Siegrist got down well to deny the attacker from close in.
The home side bounced back, though, as Clark was denied a double by a well-timed Lee Ashcroft block in the box following Pawlett’s cutback.
Second-half sub Nisbet threatened to claw one back for Stevie Crawford’s men but his volley into the ground bounced over on 66 minutes.
On 74 minutes Dunfermline came even closer, this time Nisbet feeding Ryan who cracked a curling effort off the crossbar.
United were able to close out the final moments, despite heavy pressure from the visitors, to snap a two-game losing streak and tighten their grip on top spot.
With Ayr United losing to Dundee on Friday night and Inverness falling to Morton, the Terrors move three points clear at the Championship summit.
Dundee United (4-2-3-1): Siegrist (GK); Smith, Robson, Reynolds (C), Brown; Butcher (Smith 90+2), Harkes; McMullan, Pawlett (Appere 69), Clark (King 79); Shankland.
Subs not used: Deniz (GK), Sporle, Stanton, Watson.
Dunfermline (4-4-2): Gill (GK); Comrie, Edwards, Martin (Devine 46), Ashcroft; Paton, Cochrane (Nisbet 61), Turner (McGill 87), Dow; Kiltie, Ryan.
Subs not used: Scully (GK), Beadling, Morrison, Coley.
Ref: Steven Reid.