"I wanted to be back as soon as I could," said Coghlan, who went 1-for-3 with two walks and a two-run single in the Cubs' 12-1 win over Seattle on Friday. "The DL stinks -- it stinks watching games and not being there and watching games on TV."
La Stella, who was batting .295 with nine doubles and two homers in 51 games with the Cubs, wasn't happy about the news, manager Joe Maddon said.
"It's about rules," Maddon said. "Coghlan was ready to come back, and Tommy had an option. You would not expect [him to take it well]. He shouldn't take it well. It's an unusual moment that we're in with so many guys."
Maddon said if he had a 27- or 28-man roster, it would be easier. He was upfront with La Stella, telling him the demotion had nothing to do with his performance.
"Normally it takes a day or two, not hours, and sometimes more than that for a player in that situation to come to terms with it and maybe somewhat accept it," Maddon said. "I don't anticipate an easy conversation. It is what it is, and it's very hard. The fact that he got it straight up matters. That's all you can do."
Coghlan had three hits, including two doubles, in his last rehab game with Double-A Tennessee. He was able to deal with any concerns about aggravating his side early in his rehab.
"You have to get over some of those mental hurdles," Coghlan said. "That was done in the first couple games. I had a checked swing and did all those things. It was key to get the timing back."
With the non-waiver Trade Deadline at 3 p.m. CT Monday, the Cubs have been looking at possible additions to the roster. Jorge Soler is another possible addition. He's rehabbing from a left hamstring strain, and just needs more at-bats to work on his timing, Maddon said.
"We bring Coghlan up, Tommy goes down -- and he's a big league hitter -- and Soler is on the horizon," Maddon said. "Of course, the [front office is] always attempting to do what they think is the right thing. It's hard to connect those dots right now."
Carrie Muskat has covered the Cubs since 1987, and for MLB.com since 2001. She writes a blog, Muskat Ramblings. You can follow her on Twitter @CarrieMuskat and listen to her podcast. This story was not subject to the approval of Major League Baseball or its clubs.