Canelo Alvarez drawing bulk of early action vs. favorite Gennady Golovkin

Gennady Golovkin is a solid favorite in his rematch with Canelo Alvarez on Saturday in Las Vegas, but the bulk of the early action at sportsbooks, including some of the largest bets, have been on the underdog.

Golovkin is a -145 favorite, with the price on Alvarez down to +125 at some sportsbooks.

In August, William Hill's Nevada sportsbook took a pair of $50,000 bets on Alvarez, contributing to lopsided overall action on the underdog heading into fight weekend. As of Thursday, 82 percent of the money wagered at William Hill's books was on Alvarez.

The two largest bets on the fight at the Westgate SuperBook in Las Vegas as of Friday afternoon -- $20,000 and $18,000 -- were both on Alvarez, driving the price on the underdog to as low as +115 at one point Thursday, and Caesars Palace said for every one bet they had taken on Golovkin, there were four on Alvarez.

The two leading middleweights battled to a 12-round draw last September in an exciting bout that most pundits believed Golovkin won. The controversial decision set the stage for this weekend's rematch at T-Mobile Arena.

In the hours leading up to the first fight, a late flurry of money on Golovkin drove his odds to -200 before the bell sounded. Bookmakers are wondering whether another weekend rush of big bets on Golovkin will show up Saturday. Some of it had already begun to appear late Friday afternoon.

The South Point sportsbook in Las Vegas said it was seeing good action on both fighters and bumped up its price on Golovkin to -150.

Johnny Avello, executive director of the Wynn race and sports books, said if the fight went off on Friday that he'd need the underdog.

"I got early money on the favorite, a couple of large, five-figure bets," Avello told ESPN on Friday. "I would consider [the bettors] pretty sharp when it comes to boxing. I didn't move the line, though, because I'm also anticipating some underdog money. I would expect quite a few large bets Saturday."

John Murray, sportsbook manager at the Westgate, said there has been less hype in Las Vegas about the rematch than there was for the first fight, which took place last September, shortly after the megabout between Floyd Mayweather and Conor McGregor.

"I feel like there's no buzz about this fight at all," Murray said. "And a couple of my sources told me that tickets are not selling well for this thing. It's kind of disappointing, because I think this is probably going to be the best fight boxing is going to put on this year."

Oddsmakers are expecting the fight to go the distance again. The over/under on the total rounds is 11.5 (-240 over) at the Westgate.