Edinson Volquez continued his perfect record against the Cubs, defeating the defending World Series champions 4-2 on Sunday afternoon at Marlins Park.
But Russell's injury overshadowed the Marlins' win to some extent.
After all, Russell was the starting shortstop in last year's All-Star Game. He also hit 21 homers and drove in 95 runs at age 22, helping the Cubs end their 108-year championship drought.
Russell said he would take a day or two to get treatment but did not know if he would get tested.
"There's a difference between when you are trying to work through something and when you are working against something," said Russell, who missed three games in mid-May due to the same issue.
"I don't think there is anything wrong. ... It's definitely frustrating."
The Cubs have certainly been frustrated by Volquez, who is 8-0 with a 3.12 ERA against Chicago in 13 career appearances.
Volquez (4-8) was wild, walking five batters, and his high pitch count led to an early exit. Still, he allowed just five hits and two runs.
He also escaped two bases-loaded situations with just one run allowed in those spots.
"I don't like it, but I had no choice," Volquez said about pitching with runners on base. "You start walking people, you get yourself in trouble."
Fortunately for the Marlins, A.J. Ramos picked up his 12th save of the season, leading a stellar effort by the bullpen.
Giancarlo Stanton hit a solo home run, his 20th long ball of the season, and Martin Prado added a two-run double to lead the Marlins (34-40), who split their four-game series against the Cubs (38-37).
Cubs left-hander Mike Montgomery (1-4), who picked up a save the last time he faced the Marlins on June 5, took the loss, allowing four hits, two walks, three runs (none earned) in six innings.
Miami opened the scoring in the first. Ichiro Suzuki reached on a fielding error by Russell. Miami cashed in with an RBI single by Marcell Ozuna -- who got his hit on the fourth straight curveball he saw -- and on Prado's two-run double.
"There was an awkward spin on the ball," Cubs manager JOe Maddon said of Russell's error. "I understand that."
Maddon said he was much more upset with a missed sign on a hit-and-run that resulted in Ian Happ getting thrown out at second base. Wilson Contreras was at that plate when the sign was missed.
"Physical mistakes, make as many as you need to," Maddon said. "But there were just a couple of other things we did today that kind of gave (the game) to them."
Chicago missed an opportunity in the second inning when Anthony Rizzo flied out to center field with two down and the bases loaded. And that was a pattern the entire game as Chicago left 11 runners on base.
"We were probably just trying too much," Maddon said. "Instead of just focusing on scoring one, we were trying to score them all. Just score one."
The Cubs cut their deficit to 3-2 with sacrifice flies by Rizzo in the fourth and Tommy La Stella in the fifth. But even there, the Cubs stranded multiple runners in those innings.
Jarlin Garcia (one inning), David Phelps (1 2/3 innings) and Ramos (1 1/3 innings) pitched scoreless relief for the Marlins, and Stanton added his insurance run in the seventh.
The Marlins have scored just 15 runs in the past six games, but they managed to split them against two 2016 playoff teams, the Washington Nationals and Chicago.
"The pitching has kept us close," said Ramos, who has just two four-out saves this season -- both against the Cubs. "But we're going to start hitting again pretty soon."
NOTES: Miami rested CF Christian Yelich and 2B Dee Gordon. Ichiro Suzuki, 43, became the oldest starting center fielder in baseball since at least 1900. ... Chicago rested CF Albert Almora. ... The Cubs have signed their first pick in this year's draft (LHP Brendon Little) and their third selection (RHP Cory Abbott). The middle of those three picks, RHP Alex Lange, is still playing his season and this weekend beat No. 1 Oregon State at the College World Series. ... Marlins RF Giancarlo Stanton leads all National League batters with 12 homers that average at least 110 mph in exit velocity. ... Chicago opens a four-game series on Monday at the Washington Nationals. ... The Marlins are off Monday and on Tuesday start a series against the New York Mets that concludes their 10-game homestand. The Marlins and Mets have split 200 games in south Florida, each winning 100.