Currently away on duty with Scotland, he does however hold the edge over his teammate when it comes to the international scene at present.
But while first-choice fly-half for this weekend's game with Italy, the 22-year-old knows he cannot afford to rest on his laurels.
Club teammate Stuart Hogg is also in the Scotland squad, and with the British and Irish Lion also able to ply his trade in the fly-half position, Weir is ready to fight for his spot.
"There is always going to be competition," Weir said.
"It doesn't matter if there is no replacement stand-off on the bench, I know I'll have a fight on my hands.
"Greig Laidlaw has played there for Scotland before and Hoggy did it for the Lions during the summer.
"But that is how it should be. You should have that pressure on your shoulders to perform."