Celtic have extended their lead at the top of the Scottish Premiership table to six points following a 4-1 win at basement side Dundee United on Friday.

Leigh Griffiths struck a brace for the Scottish champions, while Jozo Simunovic and Kris Commons were also on the scoresheet for the Hoops.

It was the visitors that took the lead on the night, Griffiths netting from close range to score his 50th goal for the club, and it was 2-0 just six minutes later when Simunovic's header from a Commons free kick found the back of the net.

Dundee, who are now 11 points adrift at the bottom, halved the deficit in the 31st minute when Simon Murray found the top corner, but Celtic made it 3-1 early in the second period through Griffiths, who could not miss from close range.

It was Celtic that continued to dominate and they had their fourth of the evening in the 56th minute when Commons sent a first-time effort past Eiji Kawashima.

Griffiths had a golden chance to score his hat-trick in stoppage time, but the striker was denied by the Dundee United stopper as it finished 4-1 at Tannadice Park.