The Twins added righthander Zack Littell and lefthanders Stephen Gonsalves and Lewis Thorpe to the 40-man roster on Monday, giving them 36 players on their major league roster.

Littell, 22, came to the Twins from the Yankees in the Jaime Garcia trade in late July. He was 19-1 with a 2.12 ERA and 142 strikeouts in 157 innings for Class A Tampa, Class AA Trenton and the Twins' Class AA team in Chattanooga.

Gonsalves, 23, was 9-5 with a 3.27 ERA and 118 strikeouts in 110 innings for Chattanooga and Class AAA Rochester. He was the team's minor league pitcher of the year last season.

Thorpe split the 2017 season between Class A Fort Myers and Chattanooga. He was 4-4 with a 2.93 ERA and 91 strikeouts in 83 innings. The native of Australia turns 22 on Thursday.

The Twins' decision to leave four roster spots open is an indication they plan to add players via trade or free agency in the coming weeks, but they also risk losing eligible prospects in the Rule 5 draft next month. Chief among them is their 2013 first-round pick, righthander Kohl Stewart, and a couple of hard-throwing relievers from the 2014 draft, second-rounder Nick Burdi and fifth-rounder Jake Reed.

Stewart, the No. 4 overall pick in 2013, has a 4.09 ERA in five minor league seasons, but he never has developed the elite strikeout ability projected for him. Burdi has missed portions of the past three seasons and underwent Tommy John elbow surgery in June.

Reed's fastball has been clocked at 97 mph, and he pitched well at Class AA Chattanooga and AAA Rochester this year, posting a 2.13 ERA. But he missed the first two months of the season because of a strained lat muscle and threw only 38 innings.

PHIL MILLER