NBC Sports produced some strong Nielsen numbers for its multi-sport, full-day “Championship Saturday” action, including the third-highest rating ever for horse racing’s Belmont Stakes and the highest-rated Game 2 on record for hockey’s Stanley Cup Final in primetime.

The Belmont Stakes, in which American Pharoah prevailed to become the first horse racing Triple Crown winner in 37 years, averaged a 12.3 overnight household rating/27 share, according to Nielsen, making it easily Saturday’s top-program as well as the top-rated pre-primetime Saturday sporting event of any kind since NBC covered the NFL playoff game between Baltimore and New England in January.

The 12.3 was down 5% from last year’s 12.9 rating for California Chrome’s attempt at the Triple Crown, but this is still the third-best overnight for a Belmont Stakes in the 28 years of Nielsen’s People Meters. The New York market, home of the Belmont Stakes, registered a 16.6 rating/36 share — up 5% from last year (15.8) and the second best score on record.

The Belmont was immediately followed by Game 2 of hockey’s Stanley Cup Final between the Chicago Blackhawks and Tampa Bay Lightning, which averaged a 4.80 household rating in Nielsen’s metered-market overnights. This is 5% higher than last year’s double-overtime game between the New York Rangers and Los Angeles Kings (4.56) and the best ever for a Game 2 of the Cup Final on any broadcast network.

Saturday’s Game 2 was up 13% from Wednesday’s Game 1 (4.23), which translated into a 1.76 rating in adults 18-49 (tops for any program on television that night) and 5.55 million viewers overall. Cabler NBC Sports Network will carry the next two games in the best-of-seven series on Monday and Wednesday, with coverage resuming on the broadcast network with Game 5 next Saturday.

Earlier in the day on NBC, Serena Williams’ three-set French Open victory against Lucie Safarova — marking Williams’ 20th career Grand Slam singles crown — registered a 1.88 metered-market rating, up 21% from last year’s final.

And prior to coverage of the Belmont Stakes on NBC, Premiere Boxing Champions action, featuring Robert “The Ghost” Guerrero’s split decision win over Aron Martinez, posted a 0.95 overnight tating — up 12% from NBC’s prior “PBC on NBC” afternoon telecast on May 23.