Manager Lloyd McClendon said Saunders was sent home Thursday prior to Triple-A Tacoma's 7-3 victory over Omaha because he was dehydrated with flu-like symptoms.
Saunders wasn't expected to play for ?two or three days,? McClendon said, which is likely to force the Mariners to make a procedural move because rehab assignments are limited to 20 days.
Saunders began his assignment Aug. 7 in his recovery from a strained left oblique suffered July 10 on a swing against Minnesota. His assignment was previously interrupted by a three-day absence for paternity leave.
One possibility would be to recall Saunders from his rehab assignment and option him to Tacoma until the Rainiers' season ends. He is hitting .257 (9-for-35) with no homers and two RBI through 10 games in his rehab assignment.
Jackson back in action
Outfielder Alex Jackson, the Mariners' top pick in the June draft, returned to Peoria's lineup Thursday in the Arizona Rookie League for the first time since July 21, when he suffered a broken bone in his left cheek.
The injury occurred when Jackson, 18, lost a ball in the lights.
Jackson served as the designated hitter and struck out in two at-bats before rain forced a suspension of the game with Peoria leading the White Sox 2-0 in the fifth inning in Glendale, Ariz.
Prior to the injury, Jackson batted .289 with two homers and 15 RBI in 20 games.
Mariners second baseman Robinson Cano said he never hesitated when asked to be part of the major-league team that heads to Japan in November for two exhibitions and a five-game series against that country's national team.
?I had a great experience in 2011 when I went to Taiwan (on a similar tour),? Cano said. ?Those are the great experiences that, as a player, you want to have.
?Everyone who's gone in the past says Japan is beautiful. I was going to go there either way. If not to play, I was going to go on vacation. Believe me, I want to go.?
Angels first baseman Albert Pujols, Orioles outfielder Adam Jones and Dodgers outfielder Yasiel Puig also have agreed to participate. The rest of the MLB team will be announced at a later date.
Outfielder Rusney Castillo, the Cuban defector who drew interest from the Mariners, agreed to a seven-year deal for $72.5 million from the Boston Red Sox, according to multiple reports.
The Red Sox, it appears, won a bidding war with Detroit. The Mariners and many other clubs dropped out as the bidding escalated. The deal is heavily backloaded, according to reports.
Castillo's deal is the richest first-time contract ever awarded to a Cuban defector. He is represented by the Roc Nation/CAA partnership, which landed Robinson Cano's 10-year deal with the Mariners for $240 million.
The Mariners evaluated Castillo, 27, as a good player who could become a very good player. But they projected a lower ceiling than other recent Cuban defectors such as Puig, Jose Abreu, and Yoenis Cespedes.
The Mariners entered their weekend series with Boston with a streak of nine straight losses at Fenway Park. ? Mariners right-hander Chris Young, who starts Saturday, hasn't pitched at Fenway Park since 2004. ? Boston Hall of Famer Carl Yastrzemski turned 75 on Friday.
Outfielder Gabby Guerrero and right-handed pitcher Taijuan Walker are among the 13 players cited by Baseball America in its latest Prospect Hot Sheet.
Guerrero, 20, was No. 5 on the list after going 12-for-26 with three homers and eight RBI in the past seven games for Hi-A High Desert.
Walker, 21, ranked No. 11 after two starts for Triple-A Tacoma in which he yielded four runs in 10 innings and struck out 16.
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