SEATTLE -- Taijuan Walker threw four innings of one-run ball and fellow Mariners prospect Patrick Kivlehan homered as the Surprise Saguaros opened the Arizona Fall League with a 5-4 loss to the Peoria Javelinas on Tuesday in Surprise, Ariz.
Walker, one of the top young arms in baseball, allowed five hits with no walks and five strikeouts in a 57-pitch start and left with a 3-1 lead. The Mariners would like the 22-year-old to get 20-25 innings of work in the AFL after missing the first half of this past season with shoulder problems that limited him to 120 1/3 innings overall, including 38 with Seattle.
Walker was 2-3 with a 2.61 ERA in eight appearances for Seattle and 7-4 with a 4.37 ERA in 16 Minor League starts, with 14 of those coming with Triple-A Tacoma.
Kivlehan, a 24-year-old infielder who played football at Rutgers before getting drafted by the Mariners in the fourth round of the '12 Draft, opened his second AFL season with a 1-for-4 outing that included a solo home run in the third inning off Royals prospect Kyle Zimmer, the fifth overall pick in the '12 Draft.
Kivlehan split the '14 season between Class A Advanced High Desert and Double-A Jackson, hitting .295 with 20 home runs and 103 RBIs, with 104 of his 138 games coming at Jackson. Kivlehan played first base in Tuesday's game, with fellow Seattle prospect D.J. Peterson opening at third base and going 1-for-3 with an RBI double and a walk.
Peterson, Seattle's first-round Draft pick in '13, is the No. 49 rated prospect in baseball by MLB.com and was named Seattle's co-Minor League Hitter of the Year after putting up a .297 average with 31 homers and 111 RBIs in 123 games with High Desert and Jackson.
Catcher John Hicks, the Mariners' other position player on the Saguaros squad, went 1-for-3 with a walk and picked a runner off first base. Hicks, 25, split last season between Jackson and Triple-A Tacoma and hit a combined .290 with five homers and 47 RBIs in 81 games.
Right-hander Stephen Landazuri, one of three other Mariners prospects on the pitching staff, took the loss after giving up four hits and three runs in the eighth inning. The 22-year-old was 6-5 with a 4.33 ERA in 19 starts for Jackson this year.
The AFL consists of six teams, with each squad made up of prospects from five different Major League clubs. Each team plays 32 games through Nov. 13.
Greg Johns is a reporter for MLB.com. Follow him on Twitter @GregJohnsMLB as well as his Mariners Musings blog. This story was not subject to the approval of Major League Baseball or its clubs.