WASHINGTON -- Chicago Cubs manager Rick Renteria didn't even wait for the question to be asked.
His team had been routed by the Washington Nationals just hours after trading two pitchers -- including Saturday's scheduled starter -- and he knew what was coming.
"(The trade) had nothing to do with any of the things that happened today, we spit out a bad ballgame," he said.
Gio Gonzalez pitched eight sparkling innings and Ryan Zimmerman tied a career high with four hits and drove in three runs as the Nationals roughed up the Cubs without recently traded Jeff Samardzija for a 13-0 victory.
Chicago was forced to start Carlos Villanueva (4-6) following the trade of Samardzija and Jason Hammel to the Oakland Athletics.
Villanueva was pulled after the first four Nationals reached base in the third inning. He was charged with four runs on five hits.
"We had an emergency for a starter and that's what I'm here for. It's a shame I couldn't go longer," Villanueva said.
"It's a difficult day overall, but it's part of our job title," he added. "Our job is to go out there and play our hearts off regardless of things that happen that's out of our control."
Chris Rusin, called up after the trade from Triple-A Iowa, was roughed up for five runs on nine hits over 3 2-3 innings.
Chicago, which got two hits from Justin Ruggiano had won four straight.
Renteria, who said he addressed the team before the game, said he there was no emotional letdown Saturday and doesn't think the trade will be an issue going forward.
"I don't. You had two things happen," Renteria said. "You had Gio who threw really well. So he stifles out offense pretty much and so that combined with us giving up a lot of runs (and) it kind of looks like 'wow - you know - what's going on?' It's just baseball."
Saying goodbye to teammates midseason is nothing new for the Cubs.
"It's always hard when this time comes around," second baseman Darwin Barney said. "We've dealt with this the last few years."
Pitcher John Russell said goodbye to Samardzija Friday night as word of the pending trade spread.
"It's not fun. I mean we've been through it before with (Matt) Garza and Feldy (Scott Feldman), and Cash (Andrew Cashner)," he said. "It's just tough to see your boys leave."
Jayson Werth and Anthony Rendon added three hits and two RBIs apiece for the Nationals.
"Somebody told me that earlier," Rendon said of the change from Samardzija to Villanueva. "I didn't even know who we were facing to begin with. I just show up."
Gonzalez (6-4) allowed four hits, while striking out seven and walked one. He was lifted after throwing 109 pitches.
"Today he didn't have the velocity he did in Chicago, but nevertheless when you can throw your breaking stuff for strikes then it makes your fastball look better," manager Matt Williams said after Gonzalez defeated Chicago for the second Saturday in a row.
He's now thrown 29 consecutive scoreless innings against Chicago and 22 overall.
After spending a month on the disabled list with shoulder inflammation, Gonzalez is 3-0 in four starts since his return.
After Scott Hairston hit for Denard Span in the seventh, Hairston went to left field and Harper shifted to center.
Harper helped build the game's first run Saturday. After Zimmerman singled leading off the second, Harper bunted him to second base and Zimmerman scored on Desmond's single.
Washington sent 10-men to the plate in the third as they broke the game open and chased Villanueva. It was his fifth start of the season in 23 appearances.
Span started the inning off with a single, and Rendon, Werth, Zimmerman, Ian Desmond and Wilson Ramos had RBI hits. Adam LaRoche scored on Rusin's wild pitch.
When Gonzalez singled in the seventh, every Washington starter had hit safely.
NOTES: Rusin, 27, was 6-10 with 3.96 ERA in 16 starts at Iowa. ... Renteria said the team will add another reliever Sunday. ... Chicago's RH Jake Arrieta (5-1, 1.81) opposes RH Jordan Zimmerman (6-4, 2.95) in Sunday's series finale.