The Edinburgh flanker was one of 10 players added to Gregor Townsend’s squad for the remainder of the NatWest 6 Nations on Monday after he was banned for three months earlier in the season, forcing him out of the start of the tournament.
Hardie, 29, was banned by Edinburgh and Scotland in November for “gross misconduct” amid allegations of cocaine use, but made his return to the game in early February and has since started two games to force his way into Townsend’s squad.
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Richie Gray also returns, along with Fraser Brown, Alex Dunbar, Zander Fagerson and Darryl Marfo following injury, while young Glasgow scrum-half George Horne has been called up for the first time.
Blair admits it would have been “silly” to ignore a player of Hardie’s pedigree after his return to action.
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“He’s a fantastic player,” said the skills coach. “He has a good pedigree and a good history playing with Scotland.
“When you have a player like that available it would be silly not to have him on board.
“He’s had his time off. He’s been helped through that and now he can focus on his rugby.”
Byron McGuigan and Lee Jones also return to the squad after suffering injuries earlier in the tournament and Magnus Bradbury has been re-selected to boost the squad ahead of their final two matches of the campaign against Ireland and Italy.
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Scotland head to Dublin on Saturday looking to back up an impressive win over England that revitalised their Six Nations hopes, and Blair says the added competition for places is healthy for the squad.
He said: “It is a boost. It increases the competition we’ve had.
“What we’ve found is that players coming in for injured players or experienced players who were unavailable have come in and done a really good job.
“It makes for interesting selection meetings when you have guys coming back who are up against guys who are in form at the moment.
“It’s a good situation.”
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It is a big ask for Scotland to take something from the game on Saturday, with the Dark Blues without a win away from home in the tournament, outside of Italy, since beating Ireland in 2010, while they have only ever won six matches away from home in the entire Six Nations.
Blair, who played in that 2010 win at Croke Park, is at a loss to explain their poor form on their travels.
“You would earn a lot of money if you knew that answer,” he said. “Historically, French teams, club and national, had huge differences between home and away games.
“Globally, it is a lot more difficult to win away from home. Chris Paterson said that he made a point of looking at the white line and thinking it’s just another pitch.”
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