Brendan Rodgers praised Celtic's "mentality and focus" after they continued their march towards another Scottish Premiership title with a convincing win over Dundee United.

With the Champions League play-off second leg at Bayern Munich looming on Tuesday, Celtic extended their domestic lead to 16 points before closest challengers Rangers visit Hearts on Sunday.

Fine first-half finishes from Callum McGregor and Jota made the difference before Adam Idah fired a sensational late third.

Manager Rodgers, whose side will attempt to overturn to a 2-1 deficit in Germany, said: "I thought we were excellent today off the back of a tough physical game in midweek. The level of the game and the quality of the goals was outstanding.

"If you don't do your work, or you look for an easy game, that's when you come unstuck.

"If you look at our results after the Champions League, it tells you the mentality and the focus that the players have to perform well, so I was really pleased."

Another clean sheet means Rodgers' side have won every home league game bar a 2-2 draw with Aberdeen, having not conceded in any other Premiership match at Celtic Park this season, while United's defeat drops them to fourth place.

With Tuesday's game in Germany on Tuesday in mind, Daizen Maeda, Nicolas Kuhn, Alistair Johnston and Arne Engels started on the bench. It made little difference.

After initially showing stiff resistance, Jim Goodwin's side afforded Celtic captain McGregor too much space. The midfielder capitalised, holding off a couple of challenges before he reversed the ball just inside Jack Walton's post.

United struggled to threaten but Allan Campbell did have one chance in front of goal that he couldn't quite get on the end of.

McGregor then went close and Jeffrey Schlupp struck a post before Jota became increasingly influential.

His reward was an excellent second. Cutting in from the left the winger found a gap to curl the ball into the far corner beyond Walton.

The visitors stuck at it but were undone again late in the second half when Idah fired home a brilliant finish from the edge of the box to seal another three points.

Quality was the difference. McGregor and Jota's goals had that and this could have been a far healthier scoreline. Idah's was the pick of the bunch as his eye for goal has been fully rediscovered.

Resting Maeda, for the most part, and Kuhn has no obvious impact. Jota started, his influence grew and he seems to be working his way back to the kind of form he showed in his first stint.

Rodgers might be tempted to find a starting role for the Portuguese winger in Munich on Tuesday but is blessed in those areas. Perhaps Maeda may be of use as the main striker given his pace and intensity but Idah's emphatic finish may counter that idea.

This was another convincing win. One in which you felt the champions had a number of gears left to find if required.

With only 12 games left, there's no sign of anything other than another league title arriving at Celtic Park come May.

In the opening quarter, Goodwin's side gave up an incredible amount of possession but retained a good structure and discipline to minimise direct threat.

One lapse, in affording McGregor a little too much space, was key to their downfall. From there, Jota stepped up to make their task a long shot.

To United's credit, they hung in and tried to get forward when possible but to little avail.

The desire was there but they could barely land a punch in the final third, like many teams domestically.

United's good work early in the season means a difficult run of results has been absorbed to a large extent.

The priority now is to capitalise on a couple of home fixtures to keep them firmly within the top six.

Celtic manager Brendan Rodgers: "Jota has shown his level since he's come back in, it's just a fitness thing really. That's why we're managing him through those moments, so today was another chance for him to get some minutes.

"I thought him and Jeff (Schlupp) combined really well on that side, so he's getting there."

Dundee United manager Jim Goodwin: "It was too easy on the edge of the box, there was no pressure on [Callum McGregor]. And for Jota, it was quite similar, really. When he comes inside the 18-yard line, we need to be engaging with him.

"This group will always keep going and give their all for the jersey. It certainly was not due to a lack of effort. It was down to quality. Sometimes you need to hold your hands up and admit you are playing the best team in the country."