Participator finished at the rear of the field as favourite in the SDRA Country Championships at Albury after failing to gain a clear run in the home straight when making what appeared to be a winning move.
It was a hard watch for connections with Participator also copping a bump at the start which put him further back in the chasing pack than anticipated.
Donnelly said it was a matter of getting on with the job with Participator and looking to make the most of the rest of his racing preparation.
"I haven't had anyone say he wasn't going to win at Albury and it was hard to take at the time.
"I'm as confident going into Wagga with him as I was going in to Albury," he said.
"I like to space his runs and he has had a while between starts. I'm very happy with him and I expect he will settle in the first three or four horses from where he is drawn in barrier two."
Jockey Danny Beasley will again ride Participator after travelling to Bendigo to partner Wagga star Another One in the Golden Mile on Saturday.
Keeping with his theory of less racing is best, Donnelly has mapped out a program for Participator he hopes can lead to more success and add to the gelding's record so far of three wins from eight starts.
"There is a suitable race for him at the Wagga Cup carnival is about a month and then a $150,000 race in Sydney after Sunday," Donnelly said.
Participator faces a tough test against some classy opponents, but at his best the lightly raced gelding may have too much class.
Riddlero and Ruban Bleu bring strong recent form into the $40,000 feature race, while stable mates Gusonic and Halo Warrior are both capable of figuring.
Topweight The Doctor's Song is having his first start for new trainer Maddison Collins, while Wichita Warrior was only two lengths off Zelago when resuming racing at Canberra.
Meanwhile, jockey Kayla Nisbet will have her first race rides since January with her best winning hope being for her father John aboard Lohnro Lily in the Benchmark 66 (1800m).
Lohnro Lily has won her past two starts, including her maiden at Wagga, and will step up in grade on Sunday.
Nisbet rode a winner at Wagga at her previous appearance on January 18.
