Beane told Epstein he liked the starting pitchers, and he was going to be aggressive in an attempt to improve the AL West leaders. Fast forward to this weekend, when Beane proved just how serious he was during that initial call.
Oakland and Chicago announced the big trade on Saturday, with Samardzija and Hammel heading to the West Coast for a package of prospects that included the A's first-round selections in each of the past two drafts.
The Athletics began the day with the best record in baseball, but Beane felt he needed to add depth to a rotation that responded well to season-ending injuries for Jarrod Parker and A.J. Griffin. Drew Pomeranz also is on the disabled list with a broken right hand.
Samardzija and Hammel join Scott Kazmir and Sonny Gray in one of the majors' best group of starting pitchers.
"We had to dig into our depth really early, and we felt like we needed two (starting pitchers)," Beane said.
Samardzija will start for the A's on Sunday. He was scheduled to pitch for the Cubs Saturday.
In somewhat of a surprise, the A's sent left-hander Tommy Milone to Triple-A Sacramento later Saturday to make room for Samardzija.
Milone was 6-0 with a 2.62 ERA over his last 11 starts and 6-3 with a 3.55 ERA in 16 starts overall.
Oakland will make a move Sunday to clear space for Hammel.
Minor leaguers Addison Russell, Billy McKinney and Dan Straily went to Chicago in another painful deal for the lowly Cubs, who have played better of late, but are still last in the NL Central. Chicago also gets a player to be named in its latest July sell-off.
The Cubs lost at least 91 games in each of the previous three years. They traded away starting pitchers Ryan Dempster and Paul Maholm in July 2012, and Matt Garza and Scott Feldman last July.
Chicago and Oakland talked about a Samardzija-for-Russell deal, but Epstein said the one-for-one framework didn't work. He spoke with Beane on Thursday night, and that's when the trade grew into the larger package.
The hard-throwing Samardzija had a 2-7 record for the Cubs, but he also had a 2.83 ERA and 103 strikeouts in 108 innings, making him one of the most coveted pitchers on the market. The former Notre Dame receiver was selected by Chicago in the fifth round in 2006.
Samardzija was slated to start Saturday's game at Washington, but Carlos Villanueva got the ball instead and Chicago recalled left-hander Chris Rusin from Triple-A Iowa.
The Cubs talked to the 29-year-old Samardzija about a contract extension, but were unable to come to an agreement. He is set to become a free agent for the first time after the 2015 season.
"Jeff has been a bit of workhorse," Beane said. "He's got a perfect health record. He's a guy that continues to develop. He's gotten better and better each year he goes out. There's a certain amount of self-confidence to take the career path that he did, and I've always sort of admired that from afar."
Hammel signed a $6 million, one-year contract with Chicago in February and went 8-5 with a 2.98 ERA and 104 strikeouts in 108 2-3 innings with the Cubs. He pitched six-plus innings in a 7-2 victory over Washington on Friday.
Hammel, who turns 32 in September, also has three career postseason starts.
"He's gotten better and better and we think now is a great time to have him," Beane said.
Information from The Associated Press was used in this report.