The Sierra Kosmos gelding was taken on twice during the 2200m trial - first by Face Value and then by Speedy Success - but trainer-driver Ali Malcolmson held off both challenges to win by half a length over Speedy Success in 2.57.5.
Space Ace, a two-win trotter, last raced at Forbury Park in early May and will resume off 10m in the 1-5 win trot on Thursday.
Special Delight is another trial winner starting at the Forbury Park meeting.
The Bettor's Delight mare showed speed from the mobile arm to head straight to the lead against her two rivals, and was never tested, pacing the 2200m in a tidy 2.48.7.
Her Mosgiel trainer, Syd Brown, was pleased to see her put together a polished performance.
''She's starting to learn the game,'' Brown said.
The 4yr-old has drawn on the outside of the second line in a 2200m mobile pace for maiden horses.
The Jinja Ninja was too quick for 2yr-old trotter Sunstar despite galloping behind the mobile in the score-up, trotting away to win by five lengths.
Tightly-assessed pacer Ballindooley was programmed to trial by himself over 2200m, but trainer Graeme Anderson said the group 3 winner tweaked an ankle on the beach yesterday morning, ruling him out of the trial.
He would give him a break today before checking the injury.
The original aim was the Tuapeka Cup on October 27, and the 3200m event could still be a possibility if Ballindooley recovered in time.
Other short-term options for Ballindooley included a start at Ashburton on the Monday of Labour Weekend, although the son of Sands A Flyin would start off 30m, and the junior free-for-all at Addington on New Zealand Cup day.
Anderson said King Kenny, who injured a suspensory in April, was back in the stable after a five-month break and would have eight weeks' jogging before Anderson planned a path for the trotter.
Montecrengle was also back in to work after a break and could be heading towards the southern country cups series.
Springbank Sam had his first run since his fourth in the 5yr-old trotting division of the Harness Jewels in June, winning a trial at Oamaru on Saturday.
The Rowe Cup runner-up will line up in the Canterbury Park Trotting Cup at Addington on October 11, although his trainer Phil Williamson is not looking any further beyond that.
The Sundon gelding started off 40m and ''sat back and ran past them'', Williamson said.
The runner-up to Springbank Sam, Yankee One, may also travel to Addington next Friday.
''Nothing's set in concrete with him, because I could do with another run for him, so I might take him to another trial.
Dwindle Mist, who finished third, will line up in a junior drivers' race at Gore on October 12, and Williamson has decided to take Dwindle Mist to Methven on Sunday, after nominations were left open.
