The Red Army powered to an 18-11 win over the reigning champions to book a Magners League Grand Final showdown with Leinster.
But McGahan had some reassuring words for the Ospreys and reckons they will continue to challenge for honours.
"I think they'll be fine," said McGahan, whose own side will hope to turn a table- topping season into a trophy-winning one in a week-and-a-half's time.
"They've invested heavily in their youth this season, have an excellent coaching group and are taking the right road. They'll be there or thereabouts as usual next season.
"As a side, they cop a lot of criticism, but they're a quality team with a good coaching staff. They're on the right path."
McGahan admitted his side would need to step-up their game to face Leinster but felt the victory over the stubborn Ospreys was the perfect preparation.
"You have to give credit to their defence," added McGahan.
"For them to hold out for so long without much possession was a big effort. They were terrific and games against them are always close. There's a terrific rivalry between both clubs."
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