This auction initiative has raised nearly $500,000 since its inception four years ago, and a significant portion of the proceeds from this year's event will go to Stand Up To Cancer, a longtime partner of Major League Baseball, its founding donor in 2008. In addition, this year's auction will benefit "Do It For Durrett," in honor of the late Texas Rangers ESPN.com reporter Richard Durrett, who passed away suddenly last year, and the YouCaring page established for Miami Marlins Sun Sentinel beat writer Juan C. Rodriguez, who is currently battling a brain tumor.
"The Ultimate Fielding Experience" will take place in Spring Training at the Roger Dean Stadium complex.
The winning bidder will join the Marlins in Spring Training and receive a fielding lesson from Miami infield instructor Perry Hill, widely recognized as one of the top instructors in the sport. All-Star second baseman Dee Gordon will be a "special guest" instructor. The participant must be between ages 6-18.
Fans also can bid on a "Meet & Greet" with Mattingly. The winning bidder will meet Mattingly prior to a Marlins-Yankees exhibition game. The package includes four tickets at Marlins Park, on either April 1 or 2, and four on-field batting practice passes. Reservations are required and parking is included in the package. Tickets will be in the baseline reserved section on either April 1 or 2.
The Stanton autographed baseball promises to attract plenty of attention, as does the Yelich bat. There also is a Yelich autographed baseball. Fans can also bid on a Gordon autographed baseball and an Ichiro Suzuki signed bat.
The auction runs through 9 p.m. ET on Thursday.
Joe Frisaro is a reporter for MLB.com. He writes a blog, called The Fish Pond. Follow him on Twitter @JoeFrisaro and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.