The Cubs have not confirmed the reports.
In the last two seasons, Chicago has signed free-agent pitchers such as Paul Maholm and Scott Feldman, and then flipped them at the non-waiver Trade Deadline for young prospects. The Cubs also dealt Ryan Dempster and Matt Garza the last two years, and were able to acquire young talent to the organization.
Hammel, 31, posted some of the best numbers of his career in 2012, going 8-6 with a 3.43 ERA in 118 innings over 20 starts for the Orioles. He took a step back in 2013, however, finishing 7-8 with a 4.97 ERA in 139 1/3 innings over 26 appearances (23 starts). Part of the problem may have been injury, as Hammel was on the disabled list because of tenderness in his right forearm.
From 2009-11, Hammel proved to be a durable back-of-the-rotation starter with the Rockies, throwing at least 170 innings in each of those three seasons while posting a 27-30 record and a 4.63 ERA, inflated by hitter-friendly Coors Field. Overall in parts of eight big league seasons with the Rays, Rockies and Orioles, the right-hander has gone 49-59 with a 4.80 ERA in 989 1/3 innings.
McDonald, 29, was limited to six games last season with the Pirates because of shoulder issues, and he posted a 2-2 record and a 5.76 ERA. The right-hander was designated for assignment in September and outrighted to Triple-A Indianapolis, but he refused that assignment and elected free agency.
The Cubs enter Spring Training with Jeff Samardzija, Travis Wood, Edwin Jackson and Jake Arrieta headlining their rotation. Chris Rusin, Justin Grimm and Carlos Villanueva also are expected to compete for a spot. Pitchers and catchers report to Mesa, Ariz., on Feb. 13.
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter @CarrieMuskat. This story was not subject to the approval of Major League Baseball or its clubs.