Resting Ryan crucial to Euro ambitions and the Irish cause

The natural leader is as priceless an asset as there is on the Leinster and Ireland rosters.

That is why there was a concern when the second row limped away from the action against Connacht on Friday night.

Coach Leo Cullen indicated that Ryan felt a kick to his calf as the reason for his removal from the scene.

An examination of the 20th-minute lineout, which led to Joe Tomane's bonus-point try, shows how Ryan acts as the lifter in behind Rhys Ruddock.

As Ruddock clutches Seán Cronin's throw, Ross Molony peals around to the rear of the developing maul and his knee contacts Ryan's calf in what appears to be the key moment of impact.

He felt comfortable enough to attempt to run it off, only giving way when realising that wasn't going to happen.

One pillar of the Ireland community, Jonathan Sexton, is making solid headway in his drive to make it back for the start of the Six Nations, although that is not yet a certainty.

It has led to fair comment that Ross Byrne should be the next man up at out-half, from the start or from the bench, given Jack Carty is down the pecking order and Joey Carbery is out with a long-term wrist problem.

The last thing Ireland coach Andy Farrell wants is to go into the Six Nations opener against Scotland without the 80-minute engine in his engine room.

The worrying sight of Ryan receiving medical attention was eased when he was seen to stay on as a spectator in the stands.

However, the 23-year-old will not be there for Leinster to take it to Lyon in the Champions Cup at The RDS on Sunday.

The lock is expected to be fit to fire against Benetton in Italy on Saturday week. At a push.

Cullen and Stuart Lancaster place an emphasis on their players being able to apply themselves on the Tuesday before game day.

This is where Leinster might take the view that Ryan would be best left out to build into the Six Nations.

The second row has a machine-like quality that is reminiscent of that ultimate professional Brad Thorn.

The studious application means he plays almost as well fresh as he does with three or four matches tucked under his belt.

Every stone is turned, and even shaken from his shoe, in order to smooth his preparation and tune any edge into an advantage.

A complicating factor could be the difference between Benetton's always willing attitude at Stadio Monigo compared to, say, Lyon's determination.

Leinster are chasing the number one seed on 19 points with Exeter Chiefs (19) for company and Toulouse (18), Ulster (17) and Racing 92 (17) hot on their heels.