Dallas Cowboys running back Phil Mafah breaks through the line during the fourth quarter against the Atlanta Falcons. Andrew Dieb-Imagn Images

Cowboys biggest winners of NFL preseason from FA steal to powerhouse rookie

Originally posted on Dallas Cowboys on SI
By Randy Gurzi | Last updated Aug 24, 2025 10:15 AM ET

The Dallas Cowboys wrapped up their preseason with a win over the Atlanta Falcons. It was a solid way to wrap things up following two losses, which were marred by offensive struggles.

While fans are ready for the regular season, and meaningful games, there were still some great moments to look back on from their work this offseason.

From surprise players to explosive rookies, here's a look at which players stood out as the biggest winners in Dallas during training camp and the 2025 NFL preseason.

Most improved: Nate Thomas, OT

Tyler Guyton's knee injury opened the door for 2024 seventh-round pick Nate Thomas, and he took full advantage. Thomas, who didn't make much noise as a rookie before being sent to the IR, emerged as the team's best option to replace Guyton at left tackle.

Dallas hopes to see Guyton back early in the season, but if not, they feel confident that Thomas can hold things down. That's a huge improvement from last year when he was fighting just to make the roster.

Biggest surprise: Kaiir Elam, CB

Dallas needed depth at cornerback with Trevon Diggs still recovering from a knee injury, and they turned to Kaiir Elam. A first-round pick in 2022, Elam was unable to live up to expectations with the Buffalo Bills, but he might have found new life with the Cowboys.

Elam made several highlight-reel plays during training camp and carried that confidence into the preseason. Now slated to start at cornerback in Week 1, Elam has easily been the biggest surprise. That's great news for the Dallas defense, which needed someone to rise to the challenge.

Top rookie: Phil Mafah, RB

Seventh-round pick Phil Mafah emerged as a legitimate threat to not only make the 53-man roster, but he could carve out a role for himself during his rookie season. Mafah gives Dallas a 234-pound bruiser who could be an excellent short-yardage back this year with the potential for more down the road.

It could come down to Mafah or veteran Miles Sanders for the final running back spot, and there's some concern that the coaching staff might lean toward the veteran. If so, it would be a huge mistake considering Mafah is only scratching the surface.