Le Mans wobbled but never caved in on Tuesday night as they edged Pinar Karsiyaka to earn a place in the Eurocup.
Having won the first leg of the Qualifying Round tie last week in Istanbul, 80-73, Le Mans returned home and prevailed 80-78.
Taylor Rochestie had 15 points and 10 assists for the winners.
The French club had many a nervous moment in this one.
With 18 seconds to play in the third quarter, Le Mans were on the outside of the Eurocup looking in because Karsiyaka led 69-59 after a Mire Chatman lay-up.
They answered with Rochestie, who delivered an alley-oop pass to France international Charles Kahudi.
The EuroBasket silver medalist slam-dunked to close the gap to 69-61.
Rochestie then started the fourth quarter with a jumper after being set up by Kahudi.
Marcellus Sommerville eventually knotted the game at 69-69 with two free-throws and Alex Acker dunked for a 71-69 Le Mans lead.
Karsiyaka kept the second leg close the rest of the way but weren't able to threaten the French side, which ended up winning two by two on the night for a nine-point triumph over the two legs.
Le Mans survived a very poor night at the free-throw line where they made just 13 of 23.
Acker finished with a team-high 19 points, Brazil international Joao Batista and Sommerville poured in 14 points apiece and Alain Koffi added 11.
While Le Mans return to the Eurocup, Karsiyaka go back to the EuroChallenge - the competition they played very well in last season.
Last season's EuroChallenge Final Four MVP of Krka Novo Mesto, Goran Ikonic, had a game-high 21 points for Karsiyaka.
Jovo Stanojevic added 16 points and eight boards in defeat.
John Jackson, Le Mans coach:
"We are really happy for the qualification. Stanojevic was in great shape, having little space they made their shots. But we succeeded to stop their fastbreaks better than last week. It was exciting. Our leaders were there and we still made it. I would like to congratulate my players at the end of a qualifying round which was not possible in Euroleague for the last two years."
Alex Acker, Le Mans player:
"We worked hard to avoid the mistakes we'd done in Izmir. They were agreessive and caused us a lot of trouble, but we did it. We played with our heart and we had a big support from our fans tonight."
Hakan Demir, Pinar Karsiyaka coach:
"We had a lot of pressure to recover the seven points deficit. When we succeeded leading by more than 10 points we started making unusual mistakes and we panicked. We wanted to make the difference too early."
Alper Saruhan, Pinar Karsiyaka player:
"We troubled them trouble with our zone but then they became tough in defense and that was the key for their victory."