Mildenberger just prevailed in a thrilling tussle with Rainbow Dreamer to edge victory by a head in the Betway Conditions Stakes at Wolverhampton.
Winning jockey Joe Fanning did his best to ensure a modest early pace increased with a circuit to go, taking Mark Johnston’s stayer briefly prominent for the first time as the field passed the stands.
It was a mid-race move which paid off as Outbox and eventual third Nate The Great took the hint and upped the tempo – to Mildenberger’s advantage by the time he moved to the lead entering the straight again.
Rainbow Dreamer, the 7-4 favourite to win this fast-track qualifier for the second year in succession, closed to produce a strong challenge in the final furlong.
But despite edging successfully through a gap between Mildenberger and Nate The Great to claim a rail position, Tom Marquand and the runner-up could not quite get to the 11-4 winner.
Mildenberger, who was turning round recent Newcastle form with Rainbow Dreamer, has therefore booked his place in the Betway All-Weather Marathon Championship at Lingfield on Good Friday.
Fanning told Sky Sports Racing: “It was a messy race – the pace kept steadying, and every time I went to go and put a bit of pressure on they kept quickening up, and then when I came back they slowed up again.
“If they’d gone a proper gallop, I’d have won (further).”
Mildenberger, second in last year’s Group Three Sagaro Stakes at Newcastle, nonetheless responded with great determination when it mattered.
Fanning, who was riding the six-year-old for only the second time, added: “Every time this guy’s won when I’ve seen him (previously), it’s been a good gallop.
“I was just worried it was slowing up a little bit for him.
“He’s a very good horse on the turf as well, and I thought he had a big shout in that kind of race.”