Solano played in his 90th game of the season on Friday night in the series opener with the Braves, and he tied a career high with four hits while scoring three runs and driving in one in the Marlins' 11-3 win.
"He's taking advantage of an opportunity," president of baseball operations Michael Hill said.
Entering Spring Training, the Marlins had planned on going with free agent Rafael Furcal. But a hamstring injury limited the veteran to just nine games. Derek Dietrich was the Opening Day second baseman, but he also was sidelined with a wrist injury.
Jordany Valdespin, Ed Lucas and Jeff Baker were other options. Enrique Hernandez, acquired from the Astros on July 31, is a potential candidate.
"When we built this club, we felt that was going to be Furcal and his veteran leadership and experience," Hill said. "Injuries have obviously limited what he can do.
"As we say, for a team to be successful, you have to be able to weather injuries and the next man up needs to step up and take advantage of the opportunity. Donovan has done that."
The question with Solano is whether he is truly an everyday player or better used in a utility role. Chances are the Marlins will explore their second-base options in the offseason, looking either to make a trade or sign a free agent.
Ideally, they'd like a speedster to lead off, so Christian Yelich, who has led off most of the season, can slide to the two-hole ahead of Giancarlo Stanton.
"It's that thing where you hope you have the personnel internally to help get you through," Hill said. "It will be a source as we continue to evaluate to see if that's the best fit for us moving forward or if we need to go outside and find another option to help us fill that."
Joe Frisaro is a reporter for MLB.com. He writes a blog, called The Fish Pond. Follow him on Twitter @JoeFrisaro. This story was not subject to the approval of Major League Baseball or its clubs.