Gregor Townsend's team will put their status as league leaders on the line at the Royal Dublin Showgrounds as they bid to record eight league wins on the bounce.
Sean Maitland's injury strain has made the kilted Kiwi an almost certain non-starter for the meeting with Joe Schmidt's men.
That has meant that the Namibian-born back, who warmed up for the trip across the Irish Sea with a touchdown for Stirling County in last weekend's Premiership match with Boroughmuir, is hoping that a place on the Warriors wing might come his way.
McGuigan said: "The trip to Leinster is the first in the final five-game sequence. So it sets the tone for the rest of the fixtures and for me that makes Saturday night the key game in the run-in.
"We follow it up with Munster coming to our place and if we can take a positive result from Leinster it would provide a huge platform into that one.
"We had built up fantastic momentum going into and through the Six Nations with the seven-game unbeaten run but it is vital we keep that going.
"There is no harder place to go to than to the European champions. But with them just two points behind us and sitting third, we know they will be wanting a win over us to get into the home play-off berths.
"A victory for us in Dublin would also damage them big time. We have to go there viewing this one as a fantastic opportunity."
The 23-year-old was a replacement for Tommy Seymour on the right wing when Glasgow faced the Heineken Cup holders back in November in a 6-0 defeat.
McGuigan admits that although he prefers an outside centre role at 13, he is more than happy to fly on the wing.
He said: "The bottom line is that I am desperate to play rugby for Glasgow so I'm not going to be too fussy.
"In the first game against Leinster I came on for Tommy Seymour on the right flank and I enjoyed that.
"Nothing gets the adrenaline going more than getting the ball out wide and seeing space open up in front of you.
"But right across the back line there is so much competition for places at Glasgow that if you do get a chance then you must make the most of it or you will be out again.
"This season has been a big learning curve for me but I knew that needed to be the case. I definitely feel my game has come on with the full-time regime."
McGuigan admits that his club cameo roles with Stirling County have been vital in keeping him ticking over ahead of the PRO12 re-start.
He said: "I think the head coach (Townsend) has been right to make sure that if players are not involved with Glasgow then they must have game time with a club in Premiership One. It has really kept me sharp."