"I slide so hard on it," said Zobrist, who exited Sunday's game in Kansas City in the fifth inning. "I've had times where it was sore, but never where I felt like it was really limiting my range, until yesterday. I'm not going to stay in the game if I feel like I can't make a play for the team."
Zobrist said he "might need to spread the love when sliding to the other knee" and modify his technique. He may also try wearing a smaller brace on his left knee.
A's manager Bob Melvin, who will start Eric Sogard at second base in Zobrist's stead, acknowledged the significance of being without one of the league's most versatile players.
"He hits in the three spot every day, so we're losing a significant guy here for a couple days," Melvin said. "It just means we've got less bullets to fire, too, over the course of a game. But over the course of a season that happens."
If Zobrist's recovery does not go well, he said he wouldn't rule out arthroscopic surgery. He underwent such a procedure back in 2005, after playing with frayed cartilage for nearly two years, but he said Monday, "This feels more minor."
"I know it's not normal, so in that regard, it's a little disconcerting," he said. "I'm disappointed right now that I'm not in the lineup, and I definitely want to feel 100 percent, and I'm not there. ... We'll see how it reacts.
"If it reacts well and I feel I can really move out there and contribute, then I'll give it a go. If not, then we'll have to give it more time."
Jane Lee is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.