Ronan O'Gara's side will face either Top 14 rivals Racing 92 or Sale Sharks in the last four.
The visitors continued their momentum as Yvan Reilhac drove over from a loose ball, but Levani Botia's try in the corner soon restored La Rochelle's cushion. Victor Vito went over to further extend the lead, with West again adding the additional points. Dany Priso scored under the posts to settle the hosts, with Ihaia West converting and also adding a penalty inside the opening 20 minutes.
Ihaia West scores 16 points with the boot for La Rochelle who hold off visitors' comeback after initially charging into 17-point lead.
Instead, his miss left it at three - and the hosts would soon open up a nine-point lead when West kicked two penalties. Forsans converted again and suddenly the deficit was just three. West converted again and at this point, 17-0 up after just 23 minutes, there appeared to be only one side with serious designs on the final four.
Ronan O'Gara's La Rochelle march on in the Champions Cup and into the semi-finals, having edged past the Top 14 leaders Montpellier 31-19.
Registering is free, faster than Jonny May, and also gets you access to commenting, personalisation, and competitions. You have 1 article left before you need to join up to read more. La Rochelle dominated the first half but Montpellier were able to work their way back into the game in the second, resulting in a narrow loss for the visitors after scores from Henry Thomas, Yvan Reilhac and Zach Mercer.
He was not their only impressive performer. Ihaia West kicked well and further tries from Dany Priso and Levani Botia sent last year's runners-up on their way ...
Botia set up the first try with a brilliant pass which was then aided by smart play by Jules Favre and Vito before Priso, their prop, finished the move off. He was not their only impressive performer. Ihaia West kicked well and further tries from Dany Priso and Levani Botia sent last yearโs runners-up on their way to the last four.