This picture was most likely taken at the old Scottsdale Stadium during spring training. The Giants have been training in Scottsdale, AZ since 1984. The new Scottsdale Stadium opened in 1992.
Robby Thompson (#113T) was a 24-year-old rookie in 1986. He finished 2nd to Todd Worrell in Rookie of the Year voting (ahead of guys like Barry Bonds, Will Clark, and Barry Larkin). Thompson played in 149 games and batted .271. He stole 12 bases but was caught 15 times. Robby spent his entire career (1986-1996) with the Giants. He actually signed with the Cleveland Indians as a free agent in 1997 but didn't play for them.
Dan Driessen (#65) was at the end of his career in 1986. He batted .188 in 16 at bats for the Giants before being released on May 1. Dan signed with the Houston Astros a month later and eventually finished his career with the St. Louis Cardinals in 1987.
Brad Wellman (#41) batted .154 in 13 at bats for the Giants in 1986. He played in 79 games for AAA Phoenix and became a free agent after the '86 season. Brad played sparingly for the LA Dodgers in 1987 then played two years for the KC Royals before calling it a career after the 1989 season.
Will Clark (#24T), like Mr. Thompson, was a rookie in 1986. The 22-year-old Clark was recalled from AAA Phoenix after playing six games there. Clark was in single-A ball in 1985. He played in 111 games for the Giants and batted .287 with 11 HR and 41 RBI. Will batted .300 or higher in 10 of his 15 seasons and never batted below .282. He played for the Giants from 1986-1993 and eventually finished his career with the St. Louis Cardinals in 2000.