The Patriots are trading quarterback Joe Milton to the Dallas Cowboys, a league source confirmed Thursday morning.

The teams will also swap draft picks, with the Patriots sending a seventh-rounder in exchange for a fifth-round compensatory selection. The league this year awarded Dallas three comp picks in the fifth round, Nos. 170, 171, and 174 overall. The Patriots had three seventh-rounders at Nos. 217, 220, and 238.

The 25-year-old Milton, drafted 193rd overall in the sixth round last year, will back up Dak Prescott. He would have been the third-string quarterback in New England, behind unquestioned starter Drake Maye and veteran Josh Dobbs. The Cowboys also have 30-year-old Will Grier on their roster.

When the Patriots signed Dobbs this offseason to a two-year, $8 million contract, with $3.8 million guaranteed, Milton’s future in New England became uncertain. Not only did he not have a path to the starting job, but he also wouldn’t be the backup.

After his two-touchdown performance in Week 18 last season, Milton expressed his belief in himself and his goal to be a starting quarterback. He completed 22 of his 29 pass attempts for 241 yards, leading the Patriots to a 23-16 victory.

“I feel like today was a great step in the right direction for my development, my future itself,” Milton said after the game. “Because you never know. The full length of the average NFL career is three years. I just try to take every rep that I get, even if it’s practice or a game, just take it seriously as much as I can. Whatever it takes, whatever I got to do, I’ll do it.”

Despite his impressive showing in his NFL debut, a substantial return seemed unlikely for the Patriots because Milton was playing against reserve players in a meaningless game. Questions about his touch and ability to see the field also remained.

But Milton’s arm strength and physical traits make him an intriguing prospect, one that will now move to Dallas.

Nicole Yang can be reached at [email protected] her @nicolecyang.