The clock had struck 66 minutes when Rónan Kelleher ran on to the pitch and then we all had to do a double take. Rather than Dan Sheehan being replaced, James Ryan was removing his head gear and walking off. Nor did he appear to be limping or in any discomfort.

Before the ensuing Leinster lineout, their pack went into a huddle, with both Kelleher and Sheehan among them. Kelleher took the throw and Scott Penny peeled away to feed the charging Sheehan who, it transpired, had moved to the backrow.

This was thinking outside the box. Why take Sheehan off every time Kelleher comes on? Why not give a world-class player the opportunity to play the full 80 minutes occasionally? If nothing else, it’s a handy contingency plan, akin to the Springboks flanker Deon Fourie doubling up as hooker and loose forward. Maybe this is being a little unfair on Leo Cullen, but it smacked of Jacques Nienaber’s influence.

Sheehan had led from the front with a typically dynamic and physical all-court display which once again demonstrated that the number on his back is relatively notional anyway, while also showcasing his superb lineout throwing.

In the 10th minute, his throw hit Max Deegan before he fed Jamison Gibson-Park, and then in the 10th phase of this attack he steamed on to the scrumhalf’s flat skip pass with an out-in line – which Brian O’Driscoll would have been proud of – to break the tackle of the Sale flanker Jacques Vermeulen and slide in between the posts.

Leinster's Dan Sheehan tackles Jacques Vermeulen of Sale Sharks at the Aviva Stadium. Photograph: Dan Clohessy/InphoLeinster’s Dan Sheehan tackles Jacques Vermeulen of Sale Sharks at the Aviva Stadium. Photograph: Dan Clohessy/Inpho

Early in the second period, after Ryan Baird began his dissection of the Sale throw, Sheehan gathered at the tail of the lineout and barrelled forward in his inimitable leg-pumping style, bumping both Sale half-backs. Seven phases later Harry Byrne and Garry Ringrose combined to release Baird and he teed up Keenan.

Baird finished himself next time before Sheehan – not for the first or last time in his career – gave another passable impression of an outside centre when taking Byrne’s offload, running straight and executing the right-to-left pass which gave Rieko Ioane a run to the line.

Sheehan was one of the carriers in the eight-phase attack which culminated in Tommy O’Brien calling for a chip by Byrne before benefiting from a wicked bounce and Marius Louw’s deflection.

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But the best was kept for last as the merit in keeping Sheehan on for the full 80 minutes was vindicated, very fittingly, as the clock moved from the 80th to the 81st minute in the game’s very last play.

This time it was Deegan who stole a Sale throw and Luke McGrath popped the ball to Sheehan, standing out from the lineout as first receiver. He was less than 20 metres from his own line with the whole Sale team in front of him.

Leinster's Dan Sheehan makes a break leading to Jamie Osborne's final try at the Aviva Stadium on Saturday. Photograph: Dan Clohessy/InphoLeinster’s Dan Sheehan makes a break leading to Jamie Osborne’s final try at the Aviva Stadium on Saturday. Photograph: Dan Clohessy/Inpho

He set off, arcing outside the Sale number eight and now his notional opposite number, before accelerating away from the Leinster 22. Approached by the Sale outside back Alex Wills around his own 10-metre line, Sheehan veered away from a second flailing tackle, which again added to the aesthetic of this barnstorming run. Running on to the Sale 10-metre line he drew the last defender, Tom O’Flaherty, and was no doubt relieved to hear Jamie Osborne on his outside and send him clear with another well-timed pass.

That was the pick of his two try assists to add to his own try and also vindicated the choice, made moments before, of Sheehan as the man of the match.

“He’s some athlete for a hooker,” said Jack Conan of Sheehan. “He’s probably the second or third fastest forward we have. Whenever he gets a sniff, he’s gone.”

Indeed, Sheehan has done a few passable impressions of a winger with some of his finishing in the corners over the years. Sheehan was still catching his breath a few minutes later when interviewed on Premier Sports but said it felt good to have played a full 80 minutes which, of course, is a rarity for him.

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His brother Bobby is cut from a near-identical cloth and really should be a professional rugby player as well, and he has regularly played the full 80 in more than 100 AIL games for UCD and Lansdowne through his ability play at both hooker and in the backrow.

The wonder is, actually, that this hasn’t been tried before with the older Sheehan, who is 27. This might even be something which Ireland will look to emulate, if only as a contingency plan.

Either way, one ventures this won’t be the last we’ll see of this ploy.