UPDATE 11:30 p.m. ET: According to Alex Speier of the Boston Globe, Yoshida told reporters he previously missed a month with a hamstring injury during his time in Japan. Speier noted that Tracy told reporters that the team wouldn't want to play shorthanded in Sunday's series finale, so an IL stint seems likely for the 33-year-old DH. 

Ahead of Saturday night's matchup at PNC Park with the Pittsburgh Pirates, the Boston Red Sox got some good news on the injury front as three key members of the lineup are set to embark on rehab assignments over the next week. However, the good fortune didn't last long for Boston as designated hitter Masataka Yoshida departed Saturday's contest with an apparent injury. 

Here's what you need to know: 

With the Red Sox leading Pittsburgh 1-0 in the top of the third inning, Yoshida stepped to the plate with second baseman Nick Sogard on first base with only one out. After looking at a center cut fastball for strike one, Yoshida ripped a hanging slider on the inside part of the plate down the right field line. 

As Yoshida hustled for the double, he appeared to come up short about halfway to second base before sliding in headfirst safely to put men on second and third with only one away. After sliding in safely, Yoshida struggled to his feet, causing interim manager Chad Tracy, an athletic trainer, and a translator to spill out of the visitors' dugout to check on the 33-year-old. 

After a brief conversation, Yoshida limped back to the dugout, replaced at second base by utility man Anthony Seigler. The Red Sox announced that the 33-year-old exited the game with left hamstring tightness. 

Yoshida has been one of the most productive members of the Boston lineup as the team has skyrocketed from the basement of the American League to comfortably within the playoff picture. In 40 games since June 13, Yoshida leads all Red Sox hitters with at least 140 plate appearances with a .305 batting average, while ranking in the top four in on-base percentage (.363, 4th), OPS (.829, 4th), and weighted runs created plus (127, 4th). 

Should Yoshdia miss time, it will be a major loss for a Boston lineup that, entering Saturday, had scored only 25 runs in their last seven games, the 11th-fewest in baseball during that stretch. 

We'll have more on Yoshida's status when Tracy meets with the media after the contest. 

Ahead of Saturday night's game, Tracy told reporters, including MassLive.com's Sean McAdam, that three injured Red Sox hitters will begin rehab assignments throughout the next week. 

Veteran shortstop Trevor Story, who has been on the injured list since May 16 after undergoing surgery to treat a sports hernia, is set to join Triple-A Worcester beginning on Sunday afternoon. 

After a much longer than anticipated absence, outfielder Roman Anthony will finally return to game action, joining Double-A Portland on Tuesday. The former No. 1 prospect in baseball has been out of the Boston lineup since May 5 after tearing a ligament in his right ring finger in the Red Sox' May 4 win over the Detroit Tigers. 

Finally, veteran utility man Isiah Kiner-Falefa will join Story in Worcester beginning on Wednesday. The 31-year-old journeyman infielder has been on the injured list since June 20 with a stress reaction in his left forearm.  

The Red Sox are 65-57 and in third place in the American League East.