It is all about the numbers for Celtic this season; 35 games unbeaten, a three-pronged attack on the domestic front and touching distance of a sixth successive title. Dundee manager Paul Hartley added a number of his own to a growing contacts book when Brendan Rodgers offered his upon their inaugural meeting, but it won’t stop the Ladbrokes Manager of the Month for February attempting to wrangle an entirely different kind of number when the teams meet on Sunday.

Depending on what happens at Pittodrie almost 24 hours earlier when Aberdeen host Hearts, Celtic could head to Dens Park for a title party. Hartley believes that Rodgers has raised the profile of the Scottish Premier League since his arrival at Celtic in June last year but his admiration for the Parkhead manager won’t prevent him from looking to engineer a result that keeps Dundee in the hunt for a place in the top six.

A win for the visitors on Sunday could give Celtic their sixth successive league title having dropped just four points from the possible 84 on offer this term. That consistency has elevated the Parkhead side into a different kind of hemisphere from those around them, but it has also invited ridicule from those on the outside looking in.

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“There has been a lot of negativity surrounding the game, not just domestically but around the national team too,” said Hartley. “Bringing him in and the quality of football that he has brought to football has been good to watch. You always want to pit your wits against the top managers and there is no doubt that Brendan is one of the top managers in Britain.

“You seen his record at Liverpool and at Swansea and for me to go up against Brendan Rodgers, it has got to be something that you enjoy. He's an outstanding manager and someone who's got a lot of time for other managers when he comes in the office. Somebody that I think you can pick the phone up to and talk to.

“Any time he's been in and we've been in his company, he's been excellent. We've had a chat and a couple of text messages. The last time he came into the office, he gave me my number straight away. That tells you the type of person that he is. He's got time for everybody involved in the game. He's done an outstanding job. He's an excellent manager and you anybody that talks about him, the way that he works and his man management, he has something about him. I think he's been an excellent addition to Scottish football. Something we that we did need.”

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Rodgers is not the only one sporting Celtic colours who has Hartley’s respect. In his playing days, Hartley and Scott Brown once glowered at one another from their vantage point on either side of the Edinburgh clubs but having been brought into the Parkhead stable by Gordon Strachan, both developed an appreciation of the other.

“When I played against him I didn’t really like him,” said Hartley. “He is one of those guys that I didn’t like when I played against him because we had such good battles but then when you are a team-mate, you appreciate him not just on the pitch – he is a real gentleman off the pitch.

“He was annoying. He did everything – he would annoy you, slag you, he would be cheeky, he would kick you but he was an outstanding prospect. We had great battles but we are good pals now. He is a guy you want in your team and he has found a new level this season. I think that comes down to the work that the manager has done with him on the training pitch.”

The focus, inevitably, falls on Celtic this weekend but Hartley remains quietly optimistic of securing the required sequence of results that will keep them in the top half of the table when the split comes.

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Hartley would enjoy being the first manager to beat Celtic domestically this term, but he is aware of the magnitude of the task that lies ahead.

“I think they're excellent and their results tell you that,” he said. “Even in some of the European games, the results tell you that. To go through the season domestically unbeaten is a fantastic achievement. They've got players who can win games on their own. They're a different teams from the ones I've faced before or been in. They're a team with real quality and energy and they've got a youthfulness about them also.

It is a massive gap because of the quality that they possess. The way that they've performed the season has been absolutely outstanding.

“I think Celtic are stretching. Financially they're stretching, they're a league above everyone else in the way that they can buy players or bring players in. Being in the Champions League definitely helps that financially. They're stretching. We know it's difficult for the rest of Scottish football, there's no getting away from that. But all we can do is try and perform the best that we can.”