Heathcote-based O'Sullivan will mark the return to metropolitan and feature racing by partnering Streitkid in the $25,000 Cogs Regional Challenge Pace Final (1720m) at Tabcorp Park Melton.

The Kate Hargreaves-trained five-year-old is coming off a stellar second-placing in his heat at Bendigo last Friday night, coming within inches of downing David Aiken's young star on the rise Reactor Now.

A narrow win to Reactor Now gave the four-year-old gelding his seventh-straight win and ninth overall in 12 career starts.

But he was forced to do it the hard way, with O'Sullivan aboard Streikid giving the son of Auckland Reactor and Whos Sorry Now plenty to mow down.

It was a courageous performance by Streikid, who started at the unbelievable odds of $91, and an effort which has O'Sullivan clearly pumped for Saturday's final, where he will again be one of the outsiders.

"I was glad to jump back on him for these heats and happy to be there for the $25,000 final at Melton on Saturday," she said.

"It's funny, I couldn't quite hold him (on Friday), he just likes to run and be out in front, but my instructions were to go back because there was quite a bit of speed off the front.

"It definitely ended up working in my favour with Enchanted Stride galloping just after the start and nothing else really went out.

"He ended up doing it all himself, I was just holding on, and he rolled to the front really easily.

"It wasn't what expected but he really gave (Reactor Now) a real run for his money.

"Reactor Now, as we know, is a really nice horse and has won seven in a row now. He was four-wide on the corner when I ran a 26 (third quarter), so it was a really huge performance."

Streitkid has drawn gate five in the final, just outside of Andy and Kate Gath's impressive Melton heat winner Eureka, with Reactor Now on the back row alongside the Julie Douglas-trained Torrid Saint, who will be driven by Ellen Tormey.

O'Sullivan, who is closing on 50 career wins after steering Rocks Roy to victory at Cranbourne on Sunday, hopes Streitkid can surprise his more fancied rivals one more time in Saturday's final.

The trip to Melton will be the second of two this week for the 21-year-old, who will drive the Jess Tubbs-trained Hector Macray in the second race at headquarters tonight (Wednesday).

"It's really nice getting back to some normalness, I'm looking forward to seeing everyone I haven't seen for a while since we've been racing in our regions," O'Sullivan said.

"Regional racing has been quite good. A lot of hobby trainers have been going a lot more winners, so it's helped splitting things up. They are getting a bit more of a go.

"It's something HRV could do again in the future for two months of the season.

"It's been a necessity for us and it's great we haven't stopped racing."

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