After missing the opening match of the new campaign, Blair has subsequently been handed cameo roles in the wins over Connacht and Ulster - coming off the bench during both victories.
But now Moffat believes the time is right to give Scotland internationalist Blair the number nine jersey for the Magners League leaders' showdown with the Heineken Cup holders.
Moffat said: "Greig Laidlaw has played very well so far this season and we are pleased with him.
"But Mike came on last Friday and made an impact - he is our captain and everybody knows just how good he is.
"We just felt this was a good week for Mike to start. He has had his pre-season later than others, so in many respects he is still getting into the season."
Centre Nick De Luca is also poised to record his first start of the new season; reclaiming the number 12 jersey from John Houston, who is selected on the bench.
He added: "Nick did well off the bench and we thought it was time he started. John Houston has played very well and probably played his best game last Friday night, but we thought the time was right for Nick to start this week."
Moffat explained that the team's early season success was a real squad effort and he anticipates every member of his 36-man playing staff making a significant contribution during the season.
Moffat said: "We are looking to carefully manage the whole squad over the course of the season because there is a lot of rugby to be played in the Magners League, Heineken Cup and in international rugby as well.
"You've got to look at the whole season. We cannot just rely on 25 players in order to achieve that. Last season I believe we used 36 players, so I'm sure we will use that amount again."
Just four months ago, Leinster last visited Murrayfield when they were crowned European champions and Moffat expects a lot of the Irish province's stellar names to return for the clash.
He said: "This week we face a completely different challenge against a team like Leinster and a lot of their big name players should be back this weekend.
"Historically, we've played well against Leinster here at Murrayfield and both teams tend to want to play open, attacking rugby which will make it an exciting encounter for spectators.
"Leinster have developed their game over the past two or three seasons and they are far more physical than they used to be.
"It is a chance for us to keep moving on. It was a good win at Ulster last weekend, but, in many respects, it was not a good performance.
"I think it should be a cracking game and we just want to keep winning and entertain our supporters in the process."
As a result of Blair's promotion into the starting line-up, Greig Laidlaw is named amongst the replacements while Alan MacDonald, who missed Friday's win at Ulster because of a virus, reclaims the blindside flanker spot.
Chris Paterson continues at full-back and the Scotland internationalist will be aiming to continue his prolific spell with the kicking tee - he has now scored from all of his previous 14 attempts.
After chalking up 47 points, Paterson is also the leading points scorer in the tournament - four points ahead of Glasgow's Dan Parks.
Club captain Simon Cross is still ruled out with a knee injury and joins long term absentees, Ross Rennie (knee) and David Callam (hip) in the treatment room.
Meanwhile, both full-back Jim Thompson and Scotland lock Jim Hamilton (both knee) are back doing light training and closer to returning to first team availability while Scotland wing Simon Webster is still ruled out with an Achilles injury.
Edinburgh Rugby Club team to play Leinster at Murrayfield (Saturday 26 September, kick-off 6.30pm)
15 Chris Paterson
14 Mark Robertson
13 Ben Cairns
12 Nick De Luca
11 Tim Visser
10 Phil Godman
9 Mike Blair (captain)
1 Kyle Traynor
2 Ross Ford
3 Geoff Cross
4 Craig Hamilton
5 Scott MacLeod
6 Alan MacDonald
7 Roddy Grant
8 Allister Hogg
Substitutes: Andrew Kelly, Allan Jacobsen, Ryan Grant/Davie Young, Steve Turnbull, Scott Newlands, Greig Laidlaw, John Houston.
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