Casey South Melbourne (5/217) punched its ticket to the Victorian Premier Cricket (VPC) finals by knocking off Ringwood (199) in round 16 and claiming its sixth win on the trot.
The Swans went out to the middle at 2/48 chasing 200 but soon lost their night watchman as Nathan Lambden (6) was bowled by Ian Holland.
However, skipper Chandrasinghe and Yash Pednekar formed a near 100-run partnership to well and truly put the game on Casey’s terms.
Chandrasinghe was incredibly patient, remaining unfazed when Pednekar (39) was caught, leaving the Swans 4/141.
The Rams appeared to throw a punch back by then picking up the wicket of Daud Malik (0) shortly after.
But like he has all season, Chandrasinghe kept his composure and batted cautiously and effectively alongside Devin Pollock (21 not out).
The pair saw Casey South Melbourne to the required total as Chandrasinghe raised the bat and notched yet another Victorian Premier century.
The skipper has scored 50 or more in four of his last five innings, including two hundreds, and is now up to 772 runs for the season at an average of 65.64.
The Swans have one more home-and-away test remaining, returning home to host eighth-placed Richmond.
Dandenong (203) was on the receiving end of a milestone moment amidst a defeat to finals-bound Melbourne (6/308) at Shepley Oval.
Resuming at 4/76 chasing 204, Melbourne saw its way through the day with star opener Farzan Chowna (84) passing 50 before being dismissed to be 5/174.
But youngster Nikki du Toit remained, batting all the way through to bringing up a remarkable unbeaten century on debut.
In a mature knock beyond his years, he reached 111 not out off 225 balls, willing his side to a comfortable victory.
Jack Harper accompanied him to the winning runs with a 90 of his own.
Noah Hurley took three wickets for the Panthers.
VIC PREMIER SUMMARY
Results R16 (two-day): Ringwood (199) def by Casey South Melbourne (5/217), Dandenong (203) def by Melbourne (6/308), Kingston Hawthorn (293) def Fitzroy Doncaster (186), Frankston Peninsula (340) def Geelong (235), Prahran (226) def by Northcote (317), Carlton (9/350d) def Camberwell (200), Richmond (9/293) draw with St Kilda (305), Greenvale (169, 0/91) def by Melbourne University (9/409d), Essendon (172) def by Footscray (6/174).
Ladder: St Kilda 65, Footscray 65, Melbourne 60, Casey South Melbourne 58, Carlton 58, Prahran 52, Northcote 51, Richmond 50, Camberwell 49, Melbourne University 40, Frankston Peninsula 38, Ringwood 37, Geelong 35, Dandenong 32, Fitzroy Doncaster 27.3, Essendon 21, Kingston Hawthorn 17, Greenvale 8.2.
Fixture R17 (two-day): Casey South Melbourne (4) v Richmond (8), Dandenong (14) v Carlton (5), Footscray (2) v Prahran (6), St Kilda (1) v Ringwood (12), Camberwell (9) v Melbourne (3), Geelong (13) v Greenvale (18), Frankston Peninsula (11) v Kingston Hawthorn (17), Northcote (7) v Melbourne University (10), Fitzroy Doncaster (15) v Essendon (16).
