Cubs: Best and worst free agent signings all-time, by position

Cubs: Free agent starting pitching can be one of the biggest gambles in baseball considering the pressure that is one them.

Best: Jon Lester

I doubt people expected different. Jon Lester signed the six-year deal with the Chicago Cubs in December, 2014 as the team was coming out of the rebuild and into contention. Theo Epstein reunited with his former Boston colleague in one of the biggest signings of the offseason. The goal was to bring in the multi-time All Star and postseason master to replicate the success he had in Boston and help bring the Cubs that elusive World Series title.

He did just that. Lester pitched to a 3.64 ERA, 3.86 FIP, 1.25 WHIP and 940 strikeouts in 171 starts as a Cub. In the postseason he was co-NLCS MVP in 2016 and won Game 5 of the World Series, beginning their historic comeback to claim the title. He was also a two-time All Star and Cy Young finalist in 2016 during his time in Chicago. The fans loved him, he loved the fans, he was worth every penny.

Worst: Danny Jackson

Jackson had a pretty decent career as an MLB pitcher. He pitched 15 years in the Majors and posted a 4.01 ERA and 3.77 FIP in 353 appearances. He also won two World Series titles Royals and Reds, and was a two-time All-Star.

However, his time with the Cubs was brutal. In 1991 he signed a four-year, $10.5 million deal to be the next ace; at the time this was a lot of money. Jackson ended up pitching in only 183 2/3 innings on the North Side and posted a dismal 5.19 ERA, 4.47 FIP, 1.6 WHIP and a 5-14 record (win-loss record actually mattered to people back then).

In July, 1992 he was traded to the Pirates for infielder Steve Buechele (who was actually halfway decent for the Cubs). Naturally after he left Chicago he followed up with some very solid seasons with Pittsburgh and Philly.