Gokhan Saki thought Khalil Rountree was easy pickings in a kickboxing fight. It was a grave miscalculation.

Rountree (6-2 MMA, 2-2 UFC) floored Saki (1-1 MMA, 1-0 UFC) in the first round with a perfectly placed left hand, spoiling Saki’s comeback after an injury scratched their first scheduled meeting.

The light heavyweight bout opened up the main card of today’s UFC 226 event at T-Mobile Arena in Las Vegas. It aired on pay-per-view following prelims on FS1 and UFC Fight Pass.

It was all over at the 1:36 mark of the opening frame. Saki tried to put one of his trademark leg kicks on Rountree’s thigh and failed to guard against the straight counter. The former K-1 champ thudded to the mat, and Rountree sealed the deal with a few well-placed hammerfists.

“I didn’t really know what to expect tonight,” Rountree said. “I think the big difference for me was not trying to. I focused on staying calm, being ready for anything. I was ready for low kicks, high kicks, clinches, getting flashed. I just wanted to keep my cool and stay ready.

“From the moment this fight got announced, I’ve taken so much crap online, which was kind of shocking. It didn’t motivate me – it just made this fight very personal for me. I wanted to go out there and fight my best fight, be the best me. I wanted to show the world what I was all about. And I did.”

Rountree is now back in the win column after a loss to Michal Oleksiejczuk that was overturned with a positive drug test from Oleksiejczuk. Saki, meanwhile, is 1-1 in the octagon after a smashing debut knockout of Henrique da Silva.

Up-to-the-minute UFC 226 results include:

• Khalil Rountree def. Gokhan Saki via knockout (punches) – Round 1, 1:36
• Paulo Costa def. Uriah Hall via TKO (punches) – Round 2, 2:38
• Raphael Assuncao def. Rob Font via unanimous decision (30-27, 30-27, 30-27)
• Drakkar Klose def. Lando Vannata via unanimous decison (30-27, 30-27, 30-27)
• Curtis Millender def. Max Griffin via unanimous decision (29-28, 29-28, 29-28)
• Dan Hooker def. Gilbert Burns via knockout (punches) – Round 1, 2:28
• Emily Whitmire def. Jamie Moyle via unanimous decison (29-28, 29-28, 29-28)

For complete coverage of UFC 226, check out the UFC Events section of the site.

(MMAjunkie’s Mike Bohn, John Morgan and Ken Hathaway contributed to this report on site in Las Vegas.)