He is returning from a self-imposed hiatus since February, after New Zealand Cricket reprimanded him for breaking protocol of drinking while recovering from injuries following an ODI against South Africa in Napier.
Firebirds rookie captain Stephen Murdoch said it wasn't am easy chase to overhaul CD's target of 342 runs but the way Ryder played made it achievable.
"With the help of Luke Woodcock it was a great result for us in the end," said Murdoch of the former international batting at No 6 with an unbeaten 69 from 133 balls with the help of No 7 and wicketkeeper Luke Ronchi scoring 36 from 43 balls with 13 overs remaining.
While Ryder kept mum, he said it was undeniable the former Napier Boys' High School pupil was the "star of the match".
"He was given an opportunity by the fact our bowlers fought hard throughout the first couple of innings as well because at times it looked like CD could get away from us.
"That left room for one of our batsmen to step up and win the game for us and that happened to be Jesse," Murdoch said, delighted with his first foray into a game as captain.
The Kieran Noema-Barnett-skippered Stags began the final day with a 266-run lead on 223-6 before Black Caps all-rounder Doug Bracewell and Will Young pushed the lead out to 341 off the new ball before declaring on 298-7 from 94.3 overs.
Taradale Cricket Club member Bracewell, who started the day on 34, struck 11 boundaries and a lusty six on his way to 85 off 94 balls before hitting one down the throat of Jeetan Patel off an Andy McKay delivery.
Bracewell then fired up as the opening seamer to send a shudder through the Jamie Siddons-coached Wellington when he dismissed former Black Cap Michael Papps for one in just the second over.
Murdoch followed in the 12th over, caught and bowled by Andrew Mathieson for 17, leaving Wellington at 34-2.
Enter Ryder who made his intentions clear to bring up his half ton in 34 minutes with five fours and two sixes from 39 balls.
Ryder and Michael Pollard got Wellington through to 97-3 before CD leggie Tarun Nethula had Pollard holing out to Jeet Ravel for 24.
Despite losing Grant Elliott soon after, Ryder kept on and brought up his hundred off 85 balls and his 150 from 126, before Heretaunga Building Society Cornwall allrounder Carl Cachopa had his scalp for 174, caught Bracewell.
The Firebirds join Otago - who beat the Canterbury Wizards yesterday - at the top of the table after the first round of play.
Whether CD had declared too early is something the Alan Hunt-coached side will ponder before their next outing against the Auckland Aces here next weekend but Murdoch felt it was "fair" because it was a higher rate than the other two innings.
"Jesse had a brilliant knock but another day we may have stumbled."
A dejected Noema-Barnett said it wasn't so much that the victory eluded them but more so the way they went about the job.
"We set them 340 in 80 overs so we have to take our hats off to them for a game well played and they were the better side chasing it."
The rookie skipper said the Stags gave Ryder a sniff and he made them pay.
"You can't afford to do that to the really good players because that was the major difference although the other guys around them played as well."
He thought while it was disrespectful to bill the match as Ryder v CD because the batsman had played well.
"He definitely had the better of us in this battle but we know we'll live to fight another day," said Noema-Barnett, who gallantly contributed 60 runs at No 5 in CD's second innings.
He felt the Stags' bowling lacked discipline "a touch" but their fielding wasn't much to write home about.
"If we concentrated on ourselves and did things differently, like taking our chances, it might have been a different story."
While the next shield match against Auckland here was a quick turnaround they would finetune their game.
He didn't anticipate any changes.
"I think it's pretty harsh on people after one game but, to be honest, on the whole I didn't think we were too bad," he said after veteran Mathew Sinclair and Cachopa scored a ton each in the first innings.