Sussex took a huge lead over Glamorgan on day three at Swansea but victory depends on enforcing the follow-on.

Richard Montgomerie hit an unbeaten 184 and Murray Goodwin 158 as Sussex raced to declare on 497-5.

And Sourav Ganguly, who fell second ball, was one of five wickets for Jason Lewry as the hosts struggled in reply.

David Hemp hit a brisk 125, adding 172 for the third wicket with Matthew Elliott (85) but at 289-7 the hosts are 58 away from making Sussex bat again.

Montgomerie had a 58-run start on Goodwin but the former Zimbabwe international still beat him to three figures.

Goodwin's century came in 136 balls with 12 fours, while Montgomerie took 256 balls and struck only nine boundaries.