Yu Darvish's struggles during the World Series for the Los Angeles Dodgers helped the Chicago Cubs pursue him in free agency, says Theo Epstein.

The Cubs signed the right-hander to a six-year, $126 million deal. Darvish allowed nine runs over 3.1 innings to the Houston Astros in the World Series last fall.

"I felt bad for him in the World Series, but I also felt it might be an opportunity if other teams overreact to that," Epstein said. "We know there's more to Yu Darvish than what happened in the World Series.

"First of all, there were a lot of reasons for what happened ... from the possibility of tipping pitches, the difficulty with the baseballs and then the Astros were red-hot. They won the World Series for a reason, but I don't think we would be doing our job if we evaluated based on a two-game sample. He's been over here for six years. He's proven himself as an elite pitcher."