Despite only 21 overs being bowled on day three, director of cricket Mark Wallace was delighted with the character displayed by the side as Glamorgan reached 218/1 to whittle Sussex's lead to just 16 runs.
Marnus Labuschagne struck his 3rd century of the season for the club, while Nick Selman hit his 2nd half-century of the match, with Wallace full of praise for the duo.
"It is the second time in three games that we have fought back with the bat like this so that's a good sign," said Wallace.
"I thought Marnus and Nick played superbly last night and again this morning to get us into a position where we're close to parity. We're disappointed to have missed so much play because of the rain because we were looking to really push on.
"It is going to be difficult now to be able to put pressure on Sussex and get a win here but it's been a positive start to the season. We've displayed a lot of character in quite a few games which shows the character of the team, and one which is still developing."