The viewership for FOX’s broadcast of Adam Kownacki’s first defeat was almost as high as the network’s audience for Kownacki’s fan-friendly slugfest with Chris Arreola.

Figures released Wednesday by Nielsen Media Research showed viewership for Kownacki’s fourth-round, technical-knockout defeat to Robert Helenius on Saturday night peaked at 1,681,000. The average audience for their short heavyweight bout, the main event of a tripleheader, was 1,675,000.

Helenius knocked down the heavily favored Kownacki with a right-left combination 30 seconds into the fourth round at Barclays Center in Brooklyn, the Polish-born Kownacki’s home borough. Kownacki got back to his feet by the time referee David Fields’ count reached four, but Helenius unloaded more than 30 punches on a mostly defenseless Kownacki, who was stopped while still standing at 1:08 of the fourth round.

His surprising loss knocked Kownacki off his path toward a title shot. The 30-year-old Kownacki (20-1, 15 KOs) hopes Helenius (30-3, 19 KOs) gives him an immediate rematch, but the 36-year-old Finnish fighter isn’t contractually obligated to do so.

Kowancki’s previous performance on FOX – a 12-round, unanimous-decision victory over Arreola on August 3 at Barclays Center – attracted a peak audience of 1,769,000 and an average audience of 1,727,000.

FOX’s three-bout broadcast Saturday night averaged 1,443,000 viewers overall. Combined with FOX Deportes’ live telecast, a total average of 1,533,000 viewers watched the entire show, which lasted two hours and 53 minutes.

In the opening bout Saturday night, Cuban heavyweight prospect Frank Sanchez (15-0, 11 KOs, 1 NC) convincingly out-boxed Philadelphia’s Joey Dawejko (20-8-4, 11 KOs) on his way to winning a 10-round unanimous decision.

In the second fight FOX aired, Nigerian heavyweight prospect Efe Ajagba (13-0, 11 KOs) beat Romanian veteran Razvan Cojanu (17-7, 9 KOs) by ninth-round TKO. Ajagba knocked down Cojanu twice – once apiece in the eighth and ninth rounds – before referee Ron Lipton halted the action at 2:46 of the ninth round.

Ajagba was way ahead on points – 80-71, 79-72 and 79-72 – entering the ninth round.

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.