Martinez has not tested positive for the virus, manager Alex Cora said.
The team said bench coach Will Venable tested positive. First base coach Tom Goodwin was in quarantine after close exposure to Venable, and quality control coach Ramon Vazquez was coaching first base.
Cora and Red Sox coaches wore masks on the field and in the dugout during Boston’s 1-0 loss to Toronto in Game 1 of a doubles program on Saturday, and some Red Sox reserves were also masked. .
“We have to take care of our squad,” Cora said after the game. “For now, we will do our best to wear masks in the canoe and, of course, inside. “
Martinez is hitting 0.284 with 21 homers and 68 RBIs in 104 games.
“He felt sick last night, he felt sick all day,” Cora said ahead of Saturday’s game.
Boston, which had lost eight of nine and lost the lead to AL East, placed rookie outfielder Jarren Duran on the COVID-19 injured list on Friday. Duran has not tested positive, Cora said.
To replace Martinez, the Red Sox have recalled receiver Connor Wong from Triple-A Worcester.
Right-hander Tanner Houck will be the 27th man on Saturday. Houck was due to start Game 2 in place of left-hander Martín Pérez, who was transferred to the reliever pen on Friday.
Information from the Associated Press was used in this report.