His father, Henry, was a National League umpire from 1956-75, and his brother, Joe, is a referee in the National Basketball Association.
Marquez, Marsh and Nelson are scheduled to be among the 15 active MLB umpires who will serve as instructors at the inaugural Major League Baseball Umpire Camps in November.
The Minor League umpires who will work the XM Satellite Radio All-Star Futures Game on July 9 at PNC Park also were announced on Wednesday. Christopher Conroy of the Eastern League will work home plate, Jeffrey Latter (Southern League) will be at first base, Jason Stein (Texas League) at second base and Ria Cortesio (Southern League) at third base.
The official scorers for the All-Star Game will be Bob Hertzel, a longtime scorer of the Pittsburgh Pirates and current sports editor of the Morgantown Dominion-Post
; Baltimore Sun
columnist Peter Schmuck, president of the Baseball Writers' Association of America, and Beaver County Times
writer John Perrotto, chairman of the Pittsburgh chapter of the BBWAA.
The fifth All-Star Game played in Pittsburgh will be televised by FOX Sports and around the world by MLB International, while ESPN Radio will provide exclusive national radio coverage, MLB.com will provide extensive online coverage and MLB Radio will provide play-by-play coverage.
The All-Star Game rosters will be released at 7 p.m. ET on Sunday, July 2. The announcement will reveal the 16 elected starters, as determined by fan balloting, and 45 pitchers and reserves, as determined by the player ballot, the two All-Star team managers -- Ozzie Guillen of the White Sox and Phil Garner of the Astros -- and Major League Baseball.
Fans once again will have the opportunity to select the final position player for each league's 32-man roster at MLB.com. The Final Vote will provide fans the opportunity to cast their votes from a list of five players from each league over a three-day period. Fans added Roy Oswalt (NL) and Scott Podsednik (AL) to the rosters with the Final Vote last summer.
For the fourth consecutive year, the league that wins the All-Star Game will receive home-field advantage during the World Series. The AL has won back-to-back-to-back Midsummer Classics since that provision was added prior to the 2003 World Series, and eight straight overall.