One who was in the limelight fairly recently is Gracie Gold, who finished 4th in women's figure skating at the 2015 Winter Olympics. She was not born in Springfield but grew up there for the most part before moving to Illinois.
Steve Rogers was a Major League Baseball pitcher who played his entire career for the Montreal Expos (before they became the Washington Nationals) and is considered perhaps the best pitcher in Expos history. He was born in Jefferson City but grew up in Springfield and graduated, I think, from Glendale High.
Scott Bailes is another former Major League Baseball pitcher who was not born in Springfield but who grew up there. He graduated from Parkview High School and, unlike Rogers, also attended college in Springfield, playing baseball for SMSU (now MSU). He made his Major League debut with the Cleveland Indians in the mid to late 1980s and later played briefly for the Angels and Rangers. He now works for the Springfield Cardinals minor league team.
Speaking of people who played baseball for SMSU, perhaps the most famous is Ryan Howard, current first baseman for the Philadelphia Phillies. A former National League MVP, he grew up in St. Louis but attended SMSU and played baseball for the Bears from 1998 to 2001.
Another St. Louis native who played baseball for SMSU and went on to star in the Major Leagues was Bill Mueller. He played for the Cubs, Giants, and one or two other teams from 1996 to 2006.
There are several other former Bear baseball players who made it to the Major Leagues, but those are probably the two most famous ones. In addition there have been a number of former MLB players who became associated with Springfield mainly after their playing days were over. These include Jerry Lumpe and Sherm Lollar (after whom the Sherm Lollar Lanes bowling alley was named), both of whom died in Springfield, and Bill Virdon, who still lives there, I believe.
Jack Jewsbury is a current Major League Soccer player who grew up in Springfield and attended Kickapoo High. He was born in Joplin.
Jackie Stiles is perhaps the best known female athlete associated with Springfield. She starred for the Lady Bears from 1998 to 2001 and is still the all-time leading career scorer in women's major college basketball. She was named Rookie of the Year in the WNBA in 2001, but a series of injuries curtailed her pro career. She is now an assistant coach, I believe, for the Bears.
Speaking of basketball players, Anthony Tolliver is a current NBA player who graduated from Kickapoo and helped the Chiefs win the state championship in 2002-2003. All five starters on that team went on to play college ball, three of whom played major college ball. One of the non-starters, an underclassman, also went on to play major college basketball. To illustrate how good the team was, Tolliver was widely considered perhaps the fourth best player on the team. I remember watching the team play Joplin High in Joplin when Tolliver and his classmates were seniors, and I was one of those who felt he was no better than the fourth best player on the team. However, he went on to Creighton University and worked very hard to get better, and the work paid off.
When I wrote about people from Springfield who went on to become famous entertainers, I mentioned that I rubbed shoulders (figuratively speaking) with Tess Harper, when she and I did our student teaching at the same time at Greenwood Laboratory School in the spring of 1972. I also rubbed shoulders, so to speak, with a future famous athlete during my student teaching at Greenwood. Payne Stewart was a freshman at Greenwood at the time, and he was a student in one of my classes. I don't remember that much about him except that I remember he was in my freshman English class. Stewart, of course, went on to become a professional golfer who won eleven PGA events, including three majors, before dying in an airplane crash in 1999. A section of Interstate 44 that runs through the north edge of Springfield is now named after Stewart.