In 1973, Pete Rose won the NL MVP award in Baseball. In previous years, winners were given new Corvettes For some reason, that changed

Found on https://www.facebook.com/groups/1393952824192849/

For years Sport Magazine would choose an MVP for each of the major sports championships and award them with a brand new Corvette. Sandy Koufax, Johnny Unitas and Frank Robinson were among the sports icons who walked away with a snazzy Corvette for their athletic accomplishments. At a time when many athletes worked in the off season to make ends meet winning a $5,000 Corvette was a significant prize.

 Strangely, in 1975 Pete Rose was given an AMC Pacer when he was awarded the MVP from Sport. Pete doesn’t look to disappointed about the Pacer, and with a salary of $175,000 he could easily afford any car he wanted
http://blog.collectorcarads.com/sport-magazine-gave-away-corvettes/05/2013/

In 1973 Pete Rose won 3 awards,  Baseball Digest Player of the Year Award,  the Most Valuable Player Award and the Player of the Month Award
In 1975 Pete Rose won 3 awards, the Hickok Belt, the Sports Illustrated Sportsman of the Year Award, and the 1975 World Series Most Valuable Player Award
http://www.baseball-almanac.com/players/awards.php?p=rosepe01

So why a Pacer, and not a Corvette? Maybe of the roughly 5 thousand convertibles made for 1975, none were available.

Local workers walked off their jobs five times in the 1970s, sometimes as part of national strikes. Work issues aside, local GMAD employees also suffered through an energy recession and struggling auto sales that caused on-and-off layoffs from January through March 1974 and again in January 1975.

Or maybe, someone hated Pete so much they wanted to snub him publicly

Pete Rose, Baseball's Charlie Hustle, page 108, 109