Lee Purdy of England failed to make the 147-pound weight limit at Friday's weigh-in, one day before he was scheduled to challenge welterweight titleholder Devon Alexander of St. Louis on Saturday night at Boardwalk Hall in Atlantic City, N.J.

The fight -- the co-feature on a Showtime card (9 p.m. ET/PT) headlined by the nontitle fight at 141 pounds between junior welterweight titlist Lamont Peterson and interim titleholder Lucas Matthysse -- still will go on.

However, Purdy is not eligible to win the title, and Alexander will retain the belt even if he loses. If Alexander wins, the fight will count as his first defense of the title he won in October and also will satisfy his mandatory obligation, according to Golden Boy Promotions, which was informed of that by the IBF, the sanctioning body whose belt Alexander holds.

Alexander stepped on the scale at Caesars Atlantic City at 146.7 pounds, but Purdy was 148 pounds on his first attempt. He had two hours to shed the pound, but when he returned to the scale having used almost the entire two hours, he had gotten down to only 147.8 pounds.

"These things happen. At least there's still a fight," Matchroom Sport promoter Barry Hearn told ESPN.com. "He took this fight on four weeks' notice. He's a good kid and a consummate pro, but there was nothing left for him to take off."

Purdy is substituting for Kell Brook, another Matchroom Sport-promoted fighter who was the mandatory challenger. But Brook suffered a stress fracture in his right foot and had to withdraw.

"We came clean and talked to [Alexander promoter] Golden Boy and agreed to a financial penalty," Hearn said. "Golden Boy was kind enough to give us this opportunity. [Purdy] wasn't going to turn the fight down. He trained the best he could. He tried to lose the weight, but I thought enough is enough. I wasn't prepared for him to do more. The health of the fighter is paramount."

However, this is the second consecutive fight for which Purdy has failed to make weight. In March, he knocked out former title challenger Cosme Rivera in the ninth round, but weighed 148¾ pounds, failing to make the 147-pound weight limit for an IBF regional title fight.

The promoters said Purdy (20-3-1, 13 KOs) will give up 10 percent of his $150,000 purse. Of the $15,000 he is losing, half will go to Alexander (24-1, 13 KOs); the other half will go to the New Jersey commission.

"We had no problems whatsoever with the financial penalty," Hearn said.

Both fighters are still subject to the IBF's mandated fight day weight check. They will re-weigh at 8 a.m. ET Saturday, and neither can be heavier than 157 pounds.

Eddie Hearn, Barry's son who runs the promotional company on a day-to-day basis, was disappointed that Purdy cannot win the title, but said, "Now he's got to go out there and make a name for himself."

As for Alexander's take on the situation, he was unmoved by Purdy's weight issues.

"He's fine, he's good," Golden Boy matchmaker Eric Gomez said. "He doesn't really care. He's just ready to fight."

Added Alexander: "It's OK. I'll still get the job done."