There's a new plunger on the baseball scene, a man coming on so strong as to create some belief his team could even catch and beat the New York Yankees this year. His name is Brad Corbett.

At 40, he is a young giant in the plastic pipes industry, having created a profitable world market for his product. He is a baseball zealot, owns the Texas Rangers and now wants a pennant bad.

Corbett has been gushing dollars into baseball's expensive free-agent market on a scale that may not match that Yankees yet, but which is getting close. He's not afraid to play. He has spent an estimated $6 million for foot-loose free agents in the last two years.

Last December, Eddie Robinson and Dan O'Brian, his baseball advisers, told Corbett he needed more hitting in the outfield.Ergo, he waived a $2.7 million bundle at Richie Zisk, and that fetched him.

So far, so good, they said, but another solid hitter in the outfield would be even better. During the major league winter meeting in Hawaii, Corbett demostrated the hustle tactic that made him a millonaire. At the Waikiki-Sheraton Hotel, he worked the mezzanine like a brush salesman. He buttonholed the delegates from the Branes, the Cubs, and Pirates, knocked their heads together with this trade proposals, arranged a whirlwind series of deals among the four teams that involved 11 players, and wound up with the one player he had come for, Al Oliver of Pittsburgh, who would be an adorment to any team.

Corbett can be both a wheeler-dealer and winer-diner. Just to make sure that Oliver and Pitcher John Matlack, another purchase, would be completely happy with the Rangers Corbett brought them to Texas for a week of royal entertainment. Unknown is whether they also got those Rolex watches he liked to give to new friends.

His acquisitions have brought Texas baseball fans to an emotional high and have them thinking Pennant. First, knock off Kansas City in the Al Wast, then the Yankees in the Play-offs, and take their chances in the World Series.

Losing to Kansas City in the AL West as they did last season won't happen again, ranger fans are certain because K. C. had that lucky 16-game winning streak and finished up winning 25 to26. Too much to repeat.

Corbett's additions to the team are impressive, in addition to the big stick men, Oliver and Zisk. In the winter of 1977, he spent big for free agent Bert Campaneries and got what many believe is the best shortstop in the league, and two solid pitchers, Doyle Alexandra nd Doc Medich.

He angered some AL club owners at different points last season by buying pitchers Dock Ellis and Paul Lindbald and outfielder Claudell Washington from Oakland for big money. "Here we are," complained one owner, "trying to squeeze Charley Finley out of the league and that crazy guy in Texas is keeping him in business."

Corbett isn't a native Texan, having merely picked up Texas habits. He migrated from New York via Wagner College. Ten year ago, he came to the attention of a Texas regional office of the Small Business Administration when he made such an effective pitch that he got a $300,00 start-up loan for his pipe business. An SBA official said, "Greatest presentation we're ever heard in this office."

As for the $2.7 million contract he gave outfielder Zisk, Corbett regards it as less than staggering. "We papored that down over 10 years," he said. In businessman's jargon, he was saying there wasn't much upfront money and that, given time, it was not such a big deal.

Corbett's reputation as a helter- skelter spender, not an accurate one, was promoted last winter when his general manager, Don O'Brain, was asked by reporters how much the Rangers might offer free-agent Larry Hisle. "Oh we just crank up the presses and start printing money," O'Brien said. He was joking. But the story received wide circulation as a comment on Corbett's willingness to spend.

The story also fetched the Rangers $25,000 fine from Bowie Kuhn for tampering with Hisle, at that time the property of Minnesota. That didn't improve Kuhn's status with Corbett, who a year before led a revolt to unseat the commissioner. Asked here if he had made 'peace with Kuhn, Corrbett said. "Are you kidding?"

Corbett's reputation as a mover and shaker is certified by the fact that only three of the original Texas Rangers remain from the team he bought four years ago. And it was to his own mild surprise that he even became a club owner.

In talking business of another nature with a Minneapolis attorney, Frank Ryan, Corbett casually said "Frank, maybe I should find some kind of hobby, like a sports team."

He was unaware that Ryan was also attorney for Bob Short, owner of the Rangers, who was trying to bail out at a profit after moving the team from Washington. So attorney Ryan was able to serve the needs of both clients, and Corbett, for 19 million, had himself an American League franchise.

The Rangers do have a winning manager. This is Billy Hunter, who took command in late June last season and spurred the Rangers to a remarkable 60-33 record for the rest of the year, even if it proved futile against the Kansas City Streakers.

But the Rangers drew 1,236,334 fans a record that doubtless inspired Corbett to spend more money. He says that this season the break-even point will be 1,750,000 home attendance. But with Ranger fans so giddy about their prospects - merely a half-million season tickets have already been sold and Corbett increasingly high on his team, his love affair with plastic pipes is being diluted.