Hearts, Rangers, Celtic - who will lead Premiership by end of Sunday?

Sunday will be his penultimate appearance at Ibrox, against a side he has scored regularly against over the years in Motherwell (15:00 kick-off). In fact, Aberdeen are the only club the right-back has netted more times against.

Rangers fans will hope for another decisive intervention from him, but the visitors have been formidable opponents under Jens Berthel Askou as they chase European qualification.

They have drawn twice with Rangers at Fir Park and had a strong claim to have won both of those games given the chances they created.

Rangers, though, have been a different beast at Ibrox under Danny Rohl, having gone 10 unbeaten in the league at home, while winning nine of those.

Motherwell are also on their worst run of the season, losing four of their last five and drawing one to drop away from the top three.

A win for Rangers would take them two points clear of Hearts and crank up the pressure on the leaders before the Edinburgh side's huge match at 16:30.

Is Edinburgh derby Hearts' toughest test?

Hearts head coach Derek McInnes has labelled Sunday's meeting with Edinburgh rivals Hibernian as their toughest test.

That might raise a few eyebrows, but you can see why. Hibs dismantled Hearts for 50 minutes at Easter Road in December, storming into a 3-0 lead.

Hearts scored twice and were pressing for an equaliser by the end, but it was one of their most bruising experiences this season as they seek a first title since 1960.

Hibs, who are chasing European football for the second straight season, have their own motivations as well as the derby bragging rights and the glee of derailing their rivals' title tilt.

Hearts' away form is also a concern. They have picked up just one point from their last four away from Tynecastle - at bottom side Livingston - which is why Rangers and Celtic have edged closer.

Given three of their final five games are on the road, that needs to improve.

Plus, if the Old Firm win, Hearts will find themselves two points behind Rangers and level with Celtic at kick-off, which will present its own psychological challenge.

When all that is considered, it is easy to see why McInnes thinks it could be his team's biggest test.

However, if they win it, the momentum boost could be huge.