Lineen believes the quality of the Ospreys squad is almost unrivalled and he has made no attempt to hide his admiration for Scott Johnson's star-studded side in the lead up to the biggest game of Glasgow's season.
And while the Warriors arrive in Swansea in fine form and in confident mood, Lineen is fully aware of the challenge they face at the home of one of the most exciting sides in world rugby.
"We're playing against a World XV," said Lineen in the build up to a mouth-watering encounter.
"Some of their players are just outstanding in the way they play the game. They bring a lot of physicality to the game and they're very confident.
"They're a real offloading team and I love watching them play, except when they play against us!
"When they were knocked out of the Heineken Cup, they rolled their sleeves up and said, 'Right, Magners League'. They shifted through the gears in the last few games.
"They're a daunting prospect but it's 22 against 22 and we'll see what we can do."
Lineen's respect for the Ospreys is obvious but that doesn't mean he sees this weekend's encounter as a lost cause. Far from it.
The New Zealand-born former Scotland international has instilled a steely resolve in his Glasgow side, the kind of attibute befitting their Warriors moniker.
Having been at the heart of the Play-Off race throughout the entire season, Glasgow themselves are full of confidence - a trait that Lineen says hasn't always come easy to the Firhill faithful.
"It's been really satisfying seeing this team gain more belief over the years because, traditionally, Scottish people look at things as a glass half empty with their self-depreciating humour!," added Lineen.
"We've got to come down with confidence and belief - it's about having that genuine belief.
"Getting to the Play-Offs is a good step forward but we don't want it to end.
"It's been a challenging season. I've been really impressed with the way the players have come together, well led by Al Kellock. This is the fruition of a few years together now.
"We're still developing and we've got a lot of youngsters and it's a huge achievement to get into the semi-finals. But that's the easy part, I suppose. Now we've got to make sure that we show that we deserve to be here and give a performance."
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