Rusin was added to the 25-man roster prior to the game to give the bullpen a fresh arm and someone who could go long after three extra-inning games in the first 10. A candidate for the fifth-starter spot, Rusin was needed quickly, and he filled in with a five-inning relief appearance in which he allowed one run on three hits.
His effort was appreciated, but the reality hit after the game when Rusin was told he was headed back to Triple-A Iowa on Saturday night. It's not clear if he packed an overnight bag or thought he was staying for an extended stretch.
"They called me and I was up ready to go and here by 11 [a.m.]," Rusin said. "Two quick flights, no delays, no problems."
Did he know it might be a one-day appearance?
"Anything can happen," Rusin said. "When they tell you to go pitch, you just go pitch. Whatever happens after that -- if they want you to stay, you stay, if they need you to go back and pick somebody else up, you do what they say."
The Cubs do have two days off next week, and were expected to recall right-handed reliever Blake Parker from Iowa on Sunday. Whether Villanueva gets another start is yet to be determined.
"'Villa' was battling, he was grinding," Cubs manager Rick Renteria said. "There were a couple plays that changed the dynamic of our defense -- we had a ball get away on a throw from the outfield and any time you have a bunt play and don't get an out, it puts you in a different position. We kept battling, 'Villa' kept trying to pitch through it and Rusin came in and did a nice job."
Rusin's effort allowed everyone else in the bullpen to regroup.
"Anything to help the team, I'm willing to do," Rusin said. "Today was to be the long guy and save the bullpen. I just went out there and ate up some innings."
Junior Lake launched the first pitch from Adam Wainwright into the left-field seats for his second home run and a quick 1-0 lead. Lake is the first Cubs player to open a game with a home run since David DeJesus did so last May 15 against the Rockies.
"He's an aggressive hitter, I should have known he was swinging there," Wainwright said of Lake. "That's OK to throw a fastball when you know they are swinging, you just have to locate your heaters. It's one of those times today where I left it over the plate."
It's only the second time Wainwright has ever served up a leadoff homer in his career; Ichiro Suzuki also did so on June 14, 2010.
The Cardinals answered in the second. Matt Adams led off with a home run to tie the game. Yadier Molina reached on an infield single that third baseman Luis Valbuena overran, and Allen Craig singled to right. One out later, Daniel Descalso hit an RBI single that center fielder Ryan Sweeney threw home, but Anthony Rizzo had trouble handling the throw. Sweeney was charged with an error and another run scored. Wainwright and Carpenter each hit RBI singles for a 4-1 lead.
After the Cubs added two runs in the fourth, the Cardinals attacked in their half, sending 10 batters to the plate and adding five more runs. The Cubs extended the inning with poorly executed plays. Descalso doubled and advanced on Wainwright's sacrifice, which Rizzo fielded and threw to third, but missed getting the force. Carpenter and Kolten Wong followed with RBI singles, and another run scored on Matt Holliday's fielder's choice despite a throw home from Valbuena. Villanueva was lifted for Rusin and he gave up a two-run single to Jay.
"The two innings were tough," Villanueva said. "I got two swinging bunts, and a couple forceouts that went the other way. Things unraveled quick. I didn't feel bad, I felt I had the stuff. They're a good team and they took advantage of our mistakes and they got me out of there quick."
Nate Schierholtz, who posted his first four-hit game of the year on Friday, and Sweeney added RBI doubles in the Chicago sixth off Wainwright, who was making his first start at home this season.
Rusin has been scheduled to start Sunday for Iowa, and he was pitching on four days rest, but said he didn't feel rushed, just felt "ready."
"Like I said in the spring, you have to be ready for any callup at any time," he said. "This time, it happened early in the season."