Wednesday afternoon, the Red Sox announced Pedroia underwent a "successful cartilage restoration" procedure on his left knee, and that "it is anticipated that Pedroia would return to games in approximately seven months."
Sox press release announces anticipated return to games for Pedroia in approximately 7 months (which would be late-May).— Alex Speier (@alexspeier) October 25, 2017
Pedroia's left knee has been an issue since last season. He hurt the knee late in 2016, then had a "partial medial meniscectomy and chondroplasty" procedure last offseason. Pedroia hurt the knee again this season, and spent two different stints on the disabled list with inflammation. He played hurt for long periods of time as well.
With Pedroia expected to be sidelined until Memorial Day or so, the Red Sox could turn to internal options like Brock Holt, Deven Marrero, or Tzu-Wei Lin at second base for the time being. The team is also said to have interest in re-signing Eduardo Nunez, who could play second in the interim. Nunez himself had knee problems at the end of the season, but did not require surgery.
The 34-year-old Pedroia hit .293/.369/.392 (101 OPS+) with seven home runs in 105 games in 2017, making it one of the worst offensive seasons in his career. His defense remained very good at second, though down a tick from his peak, which isn't surprisingly five the knee. Pedroia is owed $56 million from 2018-21.