ARLINGTON, Texas -- Three-time Cy Young Award winner Max Scherzer has been scratched from his scheduled start for the Texas Rangers on Saturday night.

It wasn't immediately clear why Scherzer was being replaced as the starter by Dane Dunning for the middle game of a series against the AL wild-card-chasing Seattle Mariners.

Scherzer (2-4, 3.95 ERA) has made only one start for the Rangers since July 30. The 40-year-old right-hander was activated from the injured list Saturday after missing 40 games with right shoulder fatigue and an arm nerve issue in his arm. He struck out six while allowing one run and four hits over four innings.

Scherzer is in the final season of his contract. The Rangers acquired him from the New York Mets in a deadline trade last summer after the pitcher agreed to opt in on that final year for this season at $43.3 million -- with New York paying $30.83 million.

After offseason back surgery, Scherzer dealt with the nerve issue during his rehab and didn't make his season debut until June 23. His nine starts this season are his fewest since seven as a rookie for Arizona in 2008.

His 3,407 career strikeouts are 11th on baseball's all-time list and second among active pitchers behind fellow three-time Cy Young winner Justin Verlander. Scherzer's 216 career wins are also second to his former teammate for active pitchers.