Montana De La Rosa first made Rachael Ostovich’s life miserable with a long jab, then finished off the job on the canvas.

After escaping a last-ditch submission from Ostovich (4-4 MMA, 1-1 UFC), De La Rosa (9-4 MMA, 2-0 UFC) turned the tables with a rear-naked choke in the third round.

The women’s flyweight bout closed out the preliminary card of today’s TUF 27 Finale event at Pearl Theatre at The Palms in Las Vegas. It aired on FS1 following additional prelims on UFC Fight Pass and ahead of a main card on FS1.

The tap came at the 4:21 mark of the final frame, bringing De La Rosa her second submission in the octagon after a debut armbar win this past December at The Ultimate Fighter 26 Finale. Ostovich goes to the loss column after a debut submission on the same card.

With a noticable height and reach advantage, Ostovich’s job was to get inside to land strikes. But De La Rosa made that a difficult task with a persistent jab. The strike made Ostovich hesitant to advance, and by the end of the first round she appeared unsure of what to do.

Ostovich found an answer early in the second by throwing more combinations, ducking under De La Rosa’s long limbs and countering. She briefly rattled her opponent with a spinning backfist. But De La Rosa tied her up in extended grappling exchanges and ended the frame with a powerful combo.

A hard flurry of punches prompted De La Rosa to seek the clinch in the third. It was there that Ostovich surprised with an explosive roll that briefly put her in position for an armbar. De La Rosa managed to survive, and won a position battle when she took the back.

After an extended fight, De La Rosa nearly got a stoppage by taking back mount and pounding away with punches. But Ostovich eventually exposed her neck, allowing De La Rosa to secure the fight-ending choke.

Up-to-the-minute TUF 27 Finale results include:

• Montana De La Rosa def. Rachael Ostovich via submission (rear-naked choke) – Round 3, 4:21
• Luis Pena def. Richie Smullen via submission (guillotine choke) – Round 1, 3:32
• John Gunther def. Allan Zuniga via majority decision (29-28, 29-28, 28-28)
• Bryce Mitchell def. Tyler Diamond via majority decision (29-28, 29-28, 28-28)
• Steven Peterson def. Matt Bessette via split decision (29-28, 28-29, 29-28)
• Gerald Meerschaert def. Oskar Piechota via technical submission (rear-naked choke) – Round 2, 4:55

For complete coverage of The Ultimate Fighter 27 Finale, 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.)