Chanderpaul was the second highest top scorer with 69, while Sarwan supported with 66 to earn West Indies a draw in their four-day, first-class match against Queensland – their only tune-up prior to the first Test.
Opener Adrian Barath top-scored with 74.
Chanderpaul and Sarwan plundered 131runs for the sixth wicket, as West Indies, trailing by 346 on first innings, reached 357 for six in their second innings when the two sides decided it was pointless to continue about an hour before the scheduled close at Allan Border Field.
Gayle, the West Indies captain, is now almost certain to be a non-starter for the opening Test against Ricky Ponting’s Baggy Greens on Thursday at the Gabba, following his mother’s hospitalisation in Kingston, and his return home to comfort her.
It means that Chanderpaul and Sarwan are the two most decorated West Indies batsmen remaining with the squad Down Under, and a huge burden of responsibility has fallen on their shoulders.
The visitors appeared to be heading for trouble at the hands of an almost third-string Queensland side, when they wobbled to 165 for four in the final hour before lunch.
But Chanderpaul and Sarwan put the side on their shoulders – in much the same way that they do for their native Guyana – and eased the growing threat with circumspect batting.
Sarwan had spent all of Friday off the field with a rash that required him to be lathered in an ointment, and showed little effects when he replaced Dwayne Bravo just before lunch. He struck eight fours from 120 balls in 2-3/4 hours including a typically languid cover drive off Nathan Rimmington.
But he was dropped at gully on 58 before he was dubiously adjudged lbw to Alister McDermott, the 18-year-old son of former Aussie tyro Craig McDermott, about half-hour before tea.
Chanderpaul had limped along in his typically unflustered manner, and smote eight fours and one six from 161 balls in a little under four hours. He smote leg-spinner Daniel Doran for his only maximum and one of his boundaries in the same over, but when he was caught at slip off Chris Simpson, West Indies endured a nervous finish to the day.
Nash had offered Simpson a return catch in the same over he dismissed Chanderpaul, but he remained unflappable for the remainder of the day to finish not out on 36, and Denesh Ramdin provided steady support with 20 not out to navigate the rough waters.
The day had started as treacherously as it finished, after West Indies continued from their overnight total of 133 for one.
Narsingh Deonarine was caught at first slip off Luke Feldman for 14, and Adrian Barath was caught behind off Nathan Rimmington for 74 in the space of four balls inside the first hour to leave West Indies 147 for three.
Dwayne Bravo delighted the small crowd with a pulled six off Doran onto the roof of the Stuart Law Stand, but he was adjudged lbw to Rimmington for 16 to pave the way for Sarwan and Chanderpaul’s rescue operation.