(Nati Harnik/AP)

Purke’s participation offers proof that he has recovered from a left shoulder injury that limited him to 52 2 /3 innings this season during his junior year at TCU. When the Nationals introduced Purke in August, he had been throwing two or three innings at a time. Purke, 21, will participate in major league spring training in February.

Rendon will not play in the Fall League, at least at the start, as he builds arm strength and improves his throwing form in the wake of a shoulder injury that forced him into a designated hitter role during his junior year at Rice. Rendon and the Nationals are confident Rendon’s shoulder has healed, but he needs to regain his full throwing ability.

The Nationals had reserved a roster spot for Rendon had he been ready for the Fall League. Instead, Zachary Walters, the infielder the Nationals acquired in the trade that sent Jason Marquis to the Arizona Diamondbacks, will go in his place.

The Nationals’ contingent will play for the Scottsdale Scorpions, the defending league champions. Here are the other Nationals minor leaguers in the Fall League:

Bryce Harper, OF (Harper, who turns 19 on Oct. 16, will be the youngest player in the league for the second year in a row.)

Derek Norris, C (Norris also played in the Fall League last year.)

Sammy Solis, LHP (Solis, the Nationals’ 2010 second-round pick, started and won the championship game last season.)

Pat Lehman, RHP

Rafael Martin, RHP