Dallas Thomas now on the hot seat

The NFL can be a cruel proving ground -- and Miami Dolphins guard Dallas Thomas found that out the hard way this weekend.

Thomas drew the tough assignment of Tampa Bay Buccaneers Pro Bowl defensive tackle Gerald McCoy in Saturday’s 20-14 exhibition win. It was a chance for Thomas, who has zero career starts, to prove he can handle the starting job at right guard against some of the league's best defensive linemen.

However, Thomas failed that test considerably against McCoy. He allowed a sack and fumble by McCoy, another hit on Dolphins quarterback Ryan Tannehill and a tackle for loss. Thomas also jumped offside in the second quarter when McCoy was not in the game. Things got so bad that "#DallasThomas" was trending on Twitter during the first half.

Thomas worked his way into the starting lineup with a good offseason. But he hasn't secured the job, and Saturday’s performance could put his starting spot in jeopardy.

Granted, McCoy gives plenty of guards trouble. But Thomas’ lack of resistances makes you wonder if the former 2013 third-round pick can hold up this season against other quality defensive tackles.

This is the NFL, and the Dolphins will face a stud defensive lineman or two every week during the regular season, including Pro Bowlers Vince Wilfork (New England Patriots) and Kyle Williams (Buffalo Bills) in Week 1 and Week 2, respectively. Miami’s coaching staff must know if Thomas can handle the grind before the games count in the standings.

The Dolphins have other options. Rookie third-round pick Billy Turner is one possibility, as well as veteran free-agent pickup Shelley Smith. Head coach Joe Philbin said after the game against Tampa Bay that he hasn’t decided on a starting lineup. Therefore, Turner and Smith could get a look in practice this week.