All three will appear on "MLB Tonight," the live, nightly studio show that will be the signature program of the new network, and "Hot Stove," a live, nightly offseason studio show, as well as other programming across MLB Network, which will launch Thursday in approximately 50 million homes as the largest network debut in cable history.
Williams, Amsinger and Heyman join a growing roster of on-air talent that includes studio hosts Matt Vasgersian and Victor Rojas; studio analysts Barry Larkin, Al Leiter, Joe Magrane, Dan Plesac and Harold Reynolds; and reporters Trenni Kusnierek and Hazel Mae.
"These new additions really help round our team into shape, and we're excited to get started," said Tony Petitti, president and chief executive officer of MLB Network. "Mitch's unique voice and perspective speaks for itself. Greg is a great addition for our studio shows and will help us direct traffic. And Jon brings a very credible voice to Hot Stove, as he's on the front lines every day reporting on baseball."
Williams, 44, most recently was the postgame analyst on Comcast Sportsnet's Phillies Post Game Live. Additionally, he was featured on the TBS Game of the Week Sunday pregame shows and served as a weekly contributor and baseball expert on 610 WIP's Angelo Cataldi morning show in Philadelphia.
Williams also hosted his own radio show, "The Wild Pitch," on the Phillies broadcast station 1210 WPHT in Philadelphia. He earned 192 saves and posted a 3.65 ERA in his 11 Major League seasons with the Texas Rangers (1986-88), Chicago Cubs (1989-90), Phillies (1991-93), Houston Astros (1994), the California Angels (1995) and the Kansas City Royals (1997).
Williams twice led his league in games pitched. Williams was an All-Star in 1989 with the National League Central champion Cubs, with whom he earned the nickname "Wild Thing." He posted a career-high 43 saves in 1993 and went 2-0 with two saves in the NL Championship Series, helping vault the Phillies into the World Series.
Amsinger most recently worked at CBS, where he served as the primary host for CBS College Sports programs, including Inside College Football and its NCAA basketball coverage. In 2008, Amsinger also hosted CBS' coverage of the Tour de France and the World Series of Video Games. Amsinger joined CSTV in 2003 as its first on-air host and has also maintained an interactive blog on the CSTV/CBS College Sports Web site.
Prior to joining CSTV, Amsinger was the sports director at WTHI-TV in Terre Haute, Ind. Before graduating from Lindenwood University in St. Charles, Mo., Amsinger served as network radio producer for the St. Louis Cardinals and the team's flagship radio station, KMOX-AM.
Heyman is a senior writer for Sports Illustrated, where he regularly writes the "Inside Baseball" column, and he also writes a baseball notes column called "The Daily Scoop" for SI.com that appears most weekdays during the baseball season and twice a week during the offseason.
Heyman came to Sports Illustrated in July 2006 after 16 years at Newsday, where he served as Yankees beat writer, baseball columnist and general sports columnist. Heyman, who developed a reputation for breaking major baseball stories while at Newsday, also appears as a baseball insider on WFAN radio and SNY in New York.
"MLB Tonight" will air live beginning at 6 p.m. ET until the final game of the night ends between Monday and Saturday, and will be based out of MLB Network's headquarters in Secaucus. The program will feature live look-ins of games in progress, updates, highlights, reporting and analysis.
"Hot Stove" will air during the offseason at 7 p.m. ET from Monday through Friday and feature news, reports and analysis of the moves clubs are making and planning in preparation for the upcoming season.