The Warriors currently top the Magners League standings after a superb first half of the season that has seen them win seven of their opening 10 games.
But their European campaign officially came to an end at the weekend with a 41-20 reverse in south west France.
Glasgow looked to be on the verge of a stunning away victory over the Basque giants as they led 20-11 with just eight minutes of the second half played at the Parc des Sports Aguilera.
Those hopes were extinguished, however, as the hosts claimed three tries in the final 15 minutes to ease home.
"If only matches could last an hour. I was delighted with the way we performed for 60 minutes, but I would rather forget what happened after that," said Lineen.
"Our discipline let us down and we gave away far too many penalties. We also had problems in the scrum after our first-choice props went off.
"That is a worrying situation as we plan for Magners League games when the main men are away on Scotland duty during the Six Nations campaign.
"On a positive front, I was thrilled with the displays of Berni Stortoni and Graeme Morrison."
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The Sweepstakes
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