Jeffrey Leonard's greatest moment as a player most likely occurred during the 1987 National League Championship Series while with the San Francisco Giants. During the seven game-long series against the St. Louis Cardinals, Leonard had five runs, ten hits, four home runs, five runs batted in, a batting average of .417, and a slugging percentage of .917. For his performance, Leonard was awarded the 1987 NLCS Most Valuable Player Award. As of 2017, Jeffrey Leonard is the last person to be named the Most Valuable Player of a League Championship Series or World Series while a member of the losing team. His four home runs tied a record shared by Bob Robertson (1971) and Steve Garvey (1978) for most home runs in a League Championship Series.