McLaren's Colombian, who in Spain returned from a two-race break after fracturing his left scapula, said the mostly healed injury was tough going at high speed Barcelona.
"When it's just a little (G) load," the 29-year-old insisted, "it doesn't matter. It should be okay here."
Montoya, meanwhile - and teammate Kimi Raikkonen - are sure to sparkle more than usual in the glitzy Principality.
Ron Dennis' team have done a deal with diamond creator Steinmetz to spell out the drivers' names with expensive stones on their crash helmets.
25-year-old Raikkonen's lid, though, is often unique at Monaco. This year, it features more black than usual, plus images of die and the logo 'Dice'n in the streets'. -GMM