CINCINNATI -- Improbable. Inconceivable. Incredible.
Gennett became the 17th player to homer four times in one game -- and perhaps the least likely. A second baseman who was claimed off waivers from the Milwaukee Brewers in late March, he began the night with 38 career home runs in five seasons, including three this year. He was averaging one home run every 46.2 plate appearances.
"It's surreal, man. It really is," the Cincinnati native said after putting on the greatest home run show in franchise history. "I'm truly blessed. I'm from here, born here. Watching all those guys play when I was little. And to do something that's never been done -- I can't put words on it."
Gennett, 5-foot-10 and 185 pounds, became the first major leaguer to have four homers, five hits and 10 RBIs in a game, according to the Elias Sports Bureau. His 17 total bases also set a franchise record, and his 10 RBIs tied the club mark.
"It's amazing, especially since he's not an every-day player for us," Reds manager Bryan Price said. "He's got power, but four homers in one game? I don't know what to tell you.
"It's very emotional. It was an honor to witness that."
Gennett gave his postgame interviews in a backup set of clothes after his game uniform -- still dripping from a douse of celebratory ice water -- was whisked away to be sent to Cooperstown.
"I was kind of laughing, to be honest with you," Gennett said of his response when he hit the fourth homer. "For a guy like me to do that is crazy -- a little short of a miracle."
Josh Hamilton was last player to hit four home runs in one game, for the Texas Rangers against the Baltimore Orioles in May 2012. The last National League player to hit four homers in one game was Shawn Green for the Los Angeles Dodgers against Milwaukee in May 2002.
Gennett, 27, was claimed off waivers late in spring training, and he has played a utility role for Cincinnati. He started in left field on Tuesday night.
He singled his first time up, then homered in four straight at-bats, including a grand slam. He became the seventh player to hit homers in four consecutive at-bats during a game, joining American Leaguers Carlos Delgado, Mike Cameron, Rocky Colavito and Lou Gehrig, along with National Leaguers Mike Schmidt and Robert Lowe (1894).
Gennett joined the Cardinals' Mark Whiten as the only players with a grand slam among four homers in a game, according to Elias. Whiten did it in 1993 at the Reds' old riverfront ballpark, driving in 12 runs that stands as the major league record.
Gennett had snapped an 0 for 19 slump during the Reds' 4-2 win over the Cardinals on Monday. He went 5-for-5 on Tuesday and raised his batting average 32 points to .302.
He hit an RBI single and his second career slam off St. Louis starter Adam Wainwright (6-4), who brought a 17-inning scoreless streak into the game but couldn't handle a team that has hit him like no other. Wainwright lasted only 3⅔ innings and gave up nine runs for just the third time in his career.
The last time? Also against Cincinnati, in 2013.
Gennett's grand slam was the first Wainwright had allowed since 2012.
"He had a career night, a great night," Wainwright said. "Guys do that now and then. He almost beat us by himself tonight."
With the crowd of 18,620 on its feet, Gennett hit a two-run drive in the eighth off John Brebbia for a place in history and his second curtain call.
"My teammates were awesome the whole time," Gennett said. "They made me know exactly what I needed to do and exactly how many homers I had at each point."
Prior to Tuesday night, the shortest span over which Gennett had hit four home runs was a 12-game span from Aug. 10 to Aug. 23, 2013, according to ESPN Stats & Information.
Information from The Associated Press was used in this report.