Barry Bonds (No. 25), San Francisco Giants
The Giants are one of the teams that only retire the jerseys of Hall of Famers, so while they haven’t reissued the number 25 since the all-time home run leader departed San Francisco in 2007, they haven’t officially hung it up for good either. Until recently, that appeared to be a major impediment for Bonds, who’s beloved by most Giants fans and on good terms with the team (he worked as a special instructor this spring). Due to his connection to performance-enhancing drugs, just 36.2% of BBWAA voters tabbed him when he first became eligible in 2013, and he gained almost no ground over the next two years. As the electorate evolves, resistance to his candidacy is dropping. He gained 17 points over the past two election cycles, and after receiving 53.8% in 2017 appears capable of reaching his destination by the time his eligibility expires in 2022.
Update: MLB.com’s Barry Bloom told me via Twitter that retirement of Bonds’ No. 25 is “part of his deal to return to the ball club as an advisor to [club CEO] Larry Baer.”
Bonds, of course, isn't the only PED-tainted player who not only is outside the Hall of Fame and hasn't had his jersey retired. Roger Clemens (No. 21 for the Red Sox and No. 22 for the Yankees), Mark McGwire (No. 25 for the A's and Cardinals) and Sammy Sosa (No. 21 for the Cubs) each of them strong statistical and sentimental cases, but there is no expectation yet that any will soon see their numbers permanently taken out of circulation.