Birthday boy Mick Withers has declared himself fit for the Bulls' Powergen Challenge Cup showdown with St Helens.

Full back Withers, who turned 30 today, has recovered from the groin problem that kept him out of the Super League thumping of Harlequins at the weekend.

The reliable Aussie will bolster his side as they travel to Knowsley Road bidding to progress to the Cup quarter-finals on Saturday.

He said: "I trained yesterday and should be all right."

Withers nearly battled on and played in London, having suffered the strain at Hull 11 days ago.

But he sat out only his second match of the season, explaining: "We thought I'd be better off giving it some extra time to heal as this week is a massive game.

"We lost at Saints in the league but we didn't really play anywhere near our best. If we do that on Saturday, stick to our game plan, then we know we can compete against them and get through to the next round."

Withers missed the club's last Challenge Cup success three years ago due to injury but helped them defeat Leeds in 2000 before going down to Saints the following campaign.

"It'd be awesome to reach another final," he said. "Realistically, we can't keep getting to finals year in, year out but we're all hoping to get there this time especially for the new guys, people like Stan (Gene) and young fellas like Brett (Ferres)."

The former Balmain Tiger is also looking to continue his good form for another reason.

Withers, who has made 168 appearances since signing in 1999, is out of contract at the end of the season.

"I've been pretty consistent this year and if I keep going, hopefully I'll get another," he said. "But it's out of my hands really, so we'll have to see."

Meanwhile, winger Marcus Bai will today find out how bad his knee injury is but he is expected to be missing for at least a month.