In 1985, Hernandez's previous cocaine use (and distribution of the drug to other players), which had been the subject of persistent rumors and the chief source of friction between Hernandez and Cardinals manager Whitey Herzog, became a matter of public record as a result of the Pittsburgh trial of drug dealer Curtis Strong. MLB Commissioner Peter Ueberroth found that Hernandez was among seven players who had used cocaine and been involved in its distribution. The players received season-long suspensions, that were commuted on condition that they donated ten percent of their base salaries to drug-abuse programs, submitted to random drug testing, and contributed 100 hours of drug-related community service. Hernandez has always maintained that his cocaine use was recreational and limited to a time when baseball players routinely used the drug and have adamantly denied he ever distributed the drug. Initially, Hernandez considered challenging Ueberroth's finding against him, but ultimately accepted the option available, which allowed him to avoid missing any playing time. Part of his reasoning was that he expected the Mets to make a World Series run in 1986.
Hernandez set a record for game-winning RBIs in 1985 with 24, a statistic that was only official from 1980–1988 (the previous record was 22 by the Chicago White Sox's Harold Baines in 1983). His career total is 129, which is also a record.
Hernandez credits his father, who played ball with Stan Musial when they were both in the Navy during World War II, for helping him out of a batting slump in 1985. His father would observe his at-bats on TV and note that when Keith was hitting well, he could see both the "1" and the "7" on his uniform on his back as he began to stride into the pitch. Not seeing both numbers meant Keith was bailing out on inside pitches, trying too hard to pull the ball, and vulnerable to outside fastballs or outside breaking pitches.
Hernandez batted over .300 seven times in his career and led the National League in runs scored (1979 & 1980), batting avg (1979), doubles (1979), on-base percentage (1980), and walks (1986) throughout his career. He also won 11 Gold Glove awards for his glovework at first base, setting a Major League record for the position that still stands. He won an MVP award and played on 2 World Series champions, one of whom he was the co-captain. He is the all-time Game-winning RBI leader, and in 1985 set the single-season record for this stat as well (this statistic was kept between 1980 and 1988). However, he never received enough support from the Baseball Writers' Association of America (BBWAA) to be elected to the Baseball Hall of Fame. In 2004, after nine years on the ballot, he received votes from fewer than 5% of the writers, thus ending his eligibility. Hernandez has been eligible for consideration for induction by the Veterans Committee since 2011 (20 years after his retirement) but has yet to be inducted. It's been said that the two issues that have hampered him were his occasional perceived lack of hustle as a Cardinal and his public history of drug use. Some also say that as a first baseman, he did not display the power numbers expected of the position. That last issue almost certainly colored Hernandez's candidacy negatively during the steroid era, when outrageous power statistics became the norm, however, it can be disputed that Hernandez did not play during the steroid era, with the era starting in the very late 1980s and Keith Hernandez's retirement from baseball after the 1990 MLB Season. However, it can also be argued that first base already had a reputation as a power-hitting position, with Hernandez's career overlapping that of slugging first basemen like Willie McCovey, Eddie Murray, and Tony Perez. First base's reputation as a power-hitting position may have also made Hernandez's stellar defense at the position less of an asset, as sluggers who can't field are generally moved to first—among players who have won at least 10 Gold Gloves, first base is the only position to have a player with 10 or more Gold Gloves who is either not in the Hall of Fame, currently on the BBWAA ballot, or not yet eligible. Hernandez was inducted into the New York Mets Hall of Fame in 1997 and was voted the Mets' all-time first baseman by fans in celebration of the team's 40th anniversary in 2002. Celebrating the 50th anniversary of the Mets, Hernandez was selected as the Mets all-time first baseman by a panel of sportswriters and broadcasters that included Marty Noble, Mike Lupica, Gary Cohen, Howie Rose among others. In the event held on June 17, 2012, Hernandez recalled how he first was upset by the trade to New York but soon acknowledged it as a refreshing change and said it "reenergized" him because of the "young talent, young guys that were hungry".