The Cubs transferred Merryweather (knee) to the 60-day injured list Sunday.

Merryweather will undergo surgery on his right knee Friday, Mike McGraw of the Chicago Daily Herald reports.

The Cubs placed Merryweather on the 15-day injured list Tuesday due to right knee tendinitis, Taylor McGregor of Marquee Sports Network reports.

The Cubs activated Merryweather (ribs) from the 60-day injured list Monday, Ryan Herrera of CHGO Sports reports.

Cubs manager Craig Counsell said Friday that Merryweather (ribs) is on track for a return by next weekend, "at the latest," Patrick Mooney of The Athletic reports.

Merryweather (ribs) is scheduled to pitch for Triple-A Iowa on Friday, Meghan Montemurro of the Chicago Tribune reports.

Merryweather (ribs) will begin a rehab assignment with Triple-A Iowa on Tuesday, Meghan Montemurro of the Chicago Tribune reports.

Merryweather (ribs) threw a live batting practice Saturday, and manager Craig Counsell said the 32-year-old right-hander will out out on rehab assignment with High-A South Bend next week, Sahadev Sharma of The Athletic reports.

Merryweather (ribs) threw live batting practice Tuesday, Andy Martinez of Marquee Sports Network reports.

Merryweather (ribs) will throw a bullpen session Friday, Taylor McGregor of Marquee Sports Network reports.