However, Red Sox manager John Farrell said he spoke with Ross on Saturday and he liked what he heard.
"He's improving, to the point where he was making requests if he could throw [Saturday], but we're still holding back any kind of physical activity," Farrell said. "Everything projects that after the re-exam on Monday, he'll start to go through some exertion testing, but he was in much better spirits [Saturday] than he was the day before. In his own words, he felt like he was turning the corner."
Ross was injured after taking numerous foul balls off his mask in a game against the Blue Jays at Fenway Park. He's been replaced on the roster by Ryan Lavarnway, who has impressed his manager during his brief callup.
"I thought he's done a very good job receiving," Farrell said. "I think he's still learning our guys on the mound in a regular-season environment -- it's different than Spring Training. He's swinging the bat with the consistency that he's had throughout his pro career and I think with more authority than he showed in Spring Training. He's a good player and he's going to be an offensive threat in this league."
A lifetime .171 hitter in parts of three seasons with the Red Sox, Lavarnway singled and hit a sacrifice fly in five plate appearances on Saturday night. He also held onto the ball in a violent collision at home plate, when burly Twins catcher Ryan Doumit tried to score on fly ball to short right field. And while the Twins were 2-for-2 on stolen bases on Saturday, Lavarnway threw out Tampa Bay's James Loney trying to steal third last Tuesday.
"I think one thing he's worked on that we saw in Tampa is the quick release and footwork with an accurate throw," Farrell said. "He's very capable behind the plate."
In other health-related notes, outfielder Shane Victorino returned to the lineup on Sunday after missing two games with a sore lower back, while shortstop Stephen Drew missed his second straight game with soreness in his mid-back.
Patrick Donnelly is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.