On June 18, 2006, Father's Day, with his father in the stands, Zimmerman hit his tenth Major League home run and his first walk-off home run when he hit a 2-run shot in the bottom of the ninth inning to beat the New York Yankees 3–2. The usually stoic Zimmerman gleefully tossed his batting helmet in the air while rounding third and leaped onto home plate as his teammates crowded around him. He later took a curtain call and tossed his batting gloves into the stands. On July 4, 2006, he hit a 3-run home run against Florida closer Joe Borowski on a two-strike pitch with two outs in the 9th inning of a game Washington was losing 4–3; the walk-off home run carried Washington to a 6–4 victory. This was Zimmerman's 12th career home run and his second walk-off. Two days later he delivered a walk-off single against the Marlins to win the game 8–7 in the 11th inning. On September 27, 2006, against the Philadelphia Phillies, Zimmerman hit his 20th home run of the season and tied the Expos/Nationals franchise record for home runs by a rookie; in 2002, Brad Wilkerson hit 20 home runs for the Montreal Expos. During his first season as the Nationals' third baseman, Zimmerman became a hometown hero and a fan favorite through his defense and ability to come through in late-inning situations. Frank Robinson once compared Zimmerman's defense to that of Brooks Robinson, a former teammate of Frank Robinson's. During the 2006 spring training, Frank Robinson said that he thought 12 homers and 60 RBIs would be a realistic goal for his rookie infielder; Zimmerman exceeded those expectations and finished with 20 home runs and 110 RBIs. Along with those two figures, he finished the 2006 season with 156 games played, 612 at-bats, .288 batting average, .352 OBP, 84 runs scored, 176 hits, 47 doubles, 3 triples, and 11 steals. He led all Major Leaguers with 10 or more bunts in bunt hit percentage, at 83.3% with 10 bunt hits. Although he was named on more ballots (29–27), Zimmerman finished second in the 2006 NL Rookie of the Year voting to Florida Marlins shortstop Hanley Ramírez in the closest Rookie of the Year vote ever. On a game that began on May 12, 2007, but ended at 1:42 am the next day (Mother's Day), Zimmerman hit a two-out bottom-of-the-ninth grand slam to rally the Nationals past the Florida Marlins, 7–3.