Ricketts made the statement during the Cubs' annual fan convention, according to ESPN.com's Jesse Rogers, saying, "Players from that era owe us a little bit of honesty. The only way to turn that page is to put everything on the table."
Although Major League Baseball never publicized a failed PED test by Sosa during his career, Michael S. Schmidt of the New York Times reported in 2009 that lawyers accessed information regarding a failed test by Sosa in 2003.
In 2016, current MLB Commissioner Rob Manfred said 2003 anonymous survey testing turned up 10 or more results that were concerning. He did not indicate who those tests belong to, per ESPN.com's Scott Lauber.
Sosa has long denied PED use and even testified under oath before Congress in 2005 that he did not use PEDs.
Despite that, Ricketts is hopeful that Sosa will be open with him moving forward, saying, "I think we have to be sympathetic to that era...but the players owe us some honesty, too."
Sosa ranks ninth on the all-time home runs list with 609.
During his 13-year stint with the Cubs from 1992 through 2004, Sosa clubbed 545 homers. He hit 60 or more home runs in a season on three occasions, including 66 in 1998, which was the same year St. Louis Cardinals first baseman Mark McGwire finished with a then-record 70.
All told, Sosa was a seven-time All-Star, six-time Silver Slugger Award winner and one-time National League MVP during his career.
Despite his impressive numbers, Sosa has not been elected to the Baseball Hall of Fame.
In 2017, Sosa was included on just 8.6 percent of Hall of Fame ballots, according to Baseball Reference.