Mets fans are up in arms over Tom Brady's appropriation of a nickname synonymous with Tom Seaver, shown pitching for the Mets in 1969. (AP)

In the battle of Tom vs. Tom, Mets fans are coming down squarely on the side of their guy.

Tom Brady landed on the wrong side of another sport’s New York fan base, angering Mets fans with his recent trademark application for a nickname -- “Tom Terrific” -- that has long belonged to Tom Seaver, one of the biggest stars of the Amazin’ Mets era.

The nickname has been applied to Brady’s football feats at various and relatively obscure times over the years, but it’s unquestionably more often identified with Seaver, the Hall of Fame pitcher and winner of 198 games (out of his 311 wins) over 12 seasons with the Mets. As news spread of the May 24 filing with the U.S. Patent and Trademark Office, Mets fans were furious with the New England Patriots quarterback, who wasn’t born when the nickname was bestowed on the right-handed pitcher.

“Go back to deflating footballs, you jerk,” Ronaldo Sosa, a 52-year-old Mets fan, told the New York Post on Sunday at Citi Field.

Another tweeted, “Tom Terrific will always be Tom Seaver to me.”

“Go back to Boston and get your own f------ name, Brady,” Dom D’Angelo, 55, told the paper.

Patriots boosters blasted back on social media, with one fan tweeting: “6 Super Bowl Rings!!!!!! TOM TERRIFIC!!!!!! 1 World Series! Tom Terrific!”

Even a longtime Yankees fan took offense, calling the application “an unsavory attempt” by Brady. “[T]his appalls me, too,” Clyde Haberman, the former New York Times columnist and editorial writer, tweeted. “That nickname has been Tom Seaver’s for decades. Brady can take a hike.”

The Mets offered deferential criticism, telling the Patent and Trademark Office “with all due respect to @TomBrady...There’s only one #TomTerrific to us.”

Brady’s TEB Capital Management company filed two trademark applications last month, with both clearly indicating commercial intent. One covers collectible trading cards, sports trading cards, posters and printed photographs; the other is for T-shirts and shirts. The applications, first publicized by Gerben Law Firm, were made on a 1B or “intent-to-use” basis, which means that the company is planning a line of products bearing the nickname. Those are in addition to the numerous trademarks for his TB12 logo and health and wellness products, as well as one for his TB12 Foundation.

The timing was “especially galling” to one Mets fan, “given Seaver’s health.” In March, Seaver’s family announced that the 74-year-old would be making no more public appearances because he has dementia.

“Tom will continue to work in his beloved vineyard at his California home, but has chosen to completely retire from public life,” his family said in a statement at that time. “The family is deeply appreciative of those who have supported Tom throughout his career, on and off the field, and who do so now by honoring his request for privacy.”

Seaver, the 1967 National League Rookie of the Year, won the NL Cy Young Award three times and compiled a 311-205 record with a 2.86 ERA, 3,640 strikeouts and 61 shutouts from 1967 to 1986. He pitched for the Mets from 1967 until 1977, when his desire for a new contract led to a feud with the team and he was traded to Cincinnati. He returned to the team for the 1983 season and also played for the Chicago White Sox and Boston Red Sox. He made 16 starts for the Red Sox in 1986, going 5-7 in his final season in baseball.

Long before Seaver became synonymous with Tom Terrific, that name referred to a cartoon character (along with his pooch, Mighty Manfred the Wonder Dog) on Terrytoons’ 1950s cartoon, which appeared on the “Captain Kangaroo” TV show. Terrytoons’ two Tom Terrific registrations have expired.

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