Facing his biggest test to date, UFC heavyweight Derrick Lewis continued to build his case as a top-10 heavyweight.

Lewis (19-4) extended his active win streak to six Sunday, as he knocked out Travis Browne at 3:12 of the second round. The heavyweight fight headlined UFC Fight Night inside Scotiabank Centre in Halifax, Nova Scotia.

The finish actually began very early in the round, when Lewis walked Browne to the fence and wobbled him with punches. Browne (18-7-1) did everything he could to survive the onslaught, as he covered up along the fence and then tied Lewis up in a clinch.

Derrick Lewis, left, survived the first round but found a way to finish Travis Browne in Round 2. Tom Szczerbowski/USA TODAY Sports

Lewis was relentless in his pursuit of the finish, however, and he dropped Browne again later in the round with a straight right to the crown of the head. Browne fell backward and was clearly finished, although referee Mario Yamasaki failed to step in right away, which resulted in Browne eating several unnecessary punches.

For Lewis, of Houston, the victory is easily the most significant of his career. The 32-year-old is now 9-2 in the UFC and has 16 career wins via knockout.

It was not all smooth sailing for Lewis, however, as he ate several hard front kicks to the body in the opening round. At several points in the first five minutes, Lewis winced and literally dropped both his arms to his midsection in pain. Browne seemed to recognize it, but wasn't able to truly capitalize.

After Lewis landed the first hard punches in the second round, Browne backed up to the fence and tried to cover up, although he ate several more hard uppercuts. He turned toward Yamasaki to motion that he was OK, but Lewis continued to swarm with follow-up punches.

Browne, 34, has now suffered three consecutive defeats and is 1-3 in his last four. He trained out of Las Vegas for this fight, but still worked with California-based striking coach Edmond Tarverdyan. It is the fifth knockout loss of his career.

Immediately after the bout, Lewis said he is looking forward to taking some time off, after fighting five times in the last 12 months.

Hendricks outpoints Lombard

Johny Hendricks, left, snapped a three-fight skid with a unanimous decision victory over Hector Lombard. Andrew Vaughan/AP

In his middleweight debut, former welterweight champion Johny Hendricks (18-6) earned a unanimous decision (30-27, 30-27, 29-28) over Hector Lombard (34-7-1), snapping a three-fight skid in the process.

It was not a dominant performance by any means, but Hendricks maintained a relatively high pace, which led to him outlanding Lombard in total strikes 85-to-45, according to Fightmetric. Somewhat surprisingly, the former NCAA Division-I wrestling champion did not score a takedown.

After struggling greatly in recent years to make the welterweight limit, Hendricks, 33, looked reinvigorated by the move up to 185 pounds. He kept a constant pressure on Lombard with leg kicks and short punches and timed several hard counter-knees as Lombard closed distance.

"The sky's the limit," Hendricks said, after the fight. "I couldn't do that [at welterweight]. I have energy! I have energy, man! I can't wait to see what I can do in the future."

Lombard, 39, landed a handful of clean shots and appeared to carry a speed advantage in the pocket, but he was simply outworked over the course of the 15-minute fight. The former Olympic judoka is winless since March 2014.

McMann makes quick work of late replacement opponent, calls for title shot

Sara McMann submitted Gina Mazany in the first round of their bantamweight bout. Andrew Vaughan/AP

Bantamweight Sara McMann (11-3) steamrolled UFC newcomer Gina Mazany (4-1), submitting her via arm-triangle just 1:14 into the fight.

Mazany, 28, accepted the fight on short notice, replacing Liz Carmouche. She missed the 135-pound weight limit and forfeited 20 percent of her purse to McMann.

McMann's Olympic wrestling background was on display early, as she took Mazany down immediately. Although Mazany managed to briefly get back up, McMann dragged her back down, moved into mount and then transitioned to the choke. It is McMann's second arm-triangle finish in a row and the fifth submission of her career.

Fighting out of South Carolina, McMann is now 4-2 since losing to Ronda Rousey in her only UFC title shot in 2014. Her only losses in the UFC have come against women who have held the title, in Rousey, Miesha Tate and Amanda Nunes.

"I want a title shot," McMann said. "Two submissions in a row and a win over a top-ranked opponent."

Markos upsets former champion Esparza

Strawweight contender Randa Markos, left, edged Carla Esparza for a split decision win at UFC Fight Night in Halifax, Canada. Tom Szczerbowski/USA TODAY Sports

Strawweight Randa Markos (7-4) picked up the biggest win of her career, outpointing former UFC champion Carla Esparza (11-4) via split decision (29-28, 29-28, 28-29).

The 115-pound fight was very close and could arguably have been scored either way. Esparza got away with a hard knee in the final round, which replays showed was illegal since Markos was technically grounded. Referee Keith Peterson missed the illegal strike, however, so judges might have taken it into consideration.

Markos, who fights out of Ontario, Canada, did well maintaining range against Esparza. She utilized the counterjab and landed several hard counter-right hands. After a slow first round, Esparza picked up intensity in the second round and nearly finished Markos via arm-triangle choke but ran out of time.

The third frame was extremely close. Esparza landed the controversial knee and also scored a late takedown. Markos landed a flurry late. For Esparza, the first-ever UFC strawweight champion, the loss drops her record in the Octagon to 2-2. Markos is 3-3.