Namajunas put on a striking show early on, but Esparza weathered the storm and proceeded to land several takedowns.
In round three, Esparza took Namajunas down once more, and worked her way into a championship cinching, rear-naked-choke.
In the card’s co-main event, Charles Oliveira repeatedly tested Jeremy Stephens with his vaunted submission game and earned the UD win.
Here are the results from the TUF 20 Finale, which went down in Las Vegas, Nevada.
Carla Esparza def. Rose Namajunas via submission (rear-naked-choke) R3, 1:26
Charles Oliveira def. Jeremy Stephens via unanimous decision (30-27, 29-28, 29-28)
Daron Cruickshank vs. KJ Noon declared no contest (Cruickshank couldn’t continue due to eye poke) R2, 0:25
Yancy Medeiros def. Joe Proctor via submission (guillotine choke) R1, 4:37
Jessica Penne def. Randa Markos via split decision (28-29, 30-27, 29-28)
Felice Herrig def. Lisa Ellis via submission (armbar) R2, 3:05
Heather Jo Clark def. Bec Rawlings via unanimous decision (29-28, 29-28, 29-28)
Joanne Calderwood def. Seo Hee Ham via (30-27, 30-27, 30-26)
Tecia Torres def. Angela Magana via unanimous decision (30-27, 30-27, 30-26)
Aisling Daly def. Alex Chambers via submission (armbar) R1, 4:53
Angela Hill def. Emily Kagan via unanimous decision (30-26, 30-26, 30-27)