The sevens specialist was very much a fringe performer last season but his recent form has given Gregor Townsend, the head coach, a welcome selection headache.
McGuigan underlined his versatility by switching from wing to centre for Sunday's Heineken Cup win over Exeter Chiefs which he described as "a big result for us".
"The pool is wide open, which can only be good for us. Exeter are a tough team - very physical - but we matched them in these departments and that is why we beat them.
"I was pleased to get a shot in the No.13 jersey in such an important match, but I will play where Gregor wants me to and where is best for the team. He had faith in me and I just hope I did enough to keep my place for the Munster challenge.
"I did take a couple of knocks on Sunday, but I will be fine for Friday if selected. It will be another enormous occasion for us and it is critical that we keep the Pro12 momentum going. Yes, we had a setback in the first half at Toulon, but we came back strongly to beat the Chiefs. We now need to take the same attitude back into the league."