A Grounder That Dies Midway to First Base : BEANBALL<i> by Tom Seaver with Herb Resnicow (William Morrow: $16.95; 224 pp.)</i>

So, what does a guy do while he’s sitting around waiting to be voted into baseball’s Hall of Fame? Well, if that person is 311-game winner Tom Seaver, he might try his hand at writing whodunits.

This would seem to be an unlikely career change for most athletes, but Seaver’s been successful in many ventures, and he is a personable, informed and well-traveled gentleman. That he should take up the novelist’s pen, as he has the broadcaster’s mike, is no great shock. In fact, he’s already written a few nonfiction books, including “The Art of Pitching” and “How I Would Pitch to Babe Ruth.”

Still, “Beanball” co-author Herb Resnicow must be quite a salesman. Not only did he convince the great right-hander--a former member of the Mets, Reds, White Sox and Red Sox--to join him on the mystery train but, in 1986, he also managed to talk Hall of Fame quarterback Fran Tarkenton into adding his name to “Murder at the Super Bowl” (PaperJacks: $3.95). He also wrote “The World Cup Murder” with soccer great Pele.

It would be nice to report that Tom Terrific’s mystery is as masterful as his pitching, but, alas, it isn’t. This has less to do with Seaver’s literary prowess, however, than it does with Resnicow’s peculiar sense of how things get done in the real world.

In his first such effort, “Murder at the Super Bowl,” it wasn’t easy to tell exactly where Tarkenton’s input ended and Resnicow’s began. “Beanball” makes it clear where that line is drawn because the books are practically identical: same plot, same suspects, same goofy characters, same dilemmas. The difference is the sport and the victims: Fran killed off a football coach, Tom ices a baseball owner.

The Resnicow formula sets forth that a professional sports team based in Brooklyn has just captured its division’s championship and, against all odds, is pitted against a heavily favored competitor for the overall league championship. Sometime before that game, however, an important member of the Brooklyn squad is killed.

Enter Marcus Aurelius Burr, an excruciatingly yuppified sportswriter who really wants to become an investigative reporter (“Uncover one major scandal and your fortune’s made. Books, movies, TV.”) Burr always manages to stumble upon the murder victim hours before anyone else and, like a true “Front Page” journalist, calls his editor before he alerts the police--which hardly endears him to the homicide boys downtown. Seaver’s and Tarkenton’s input seems to come chiefly in providing sports color and inventing game strategy.

Well, it’s not Travis McGee, but so far, so good. The problem--and it’s a huge one--comes in the fact that Resnicow hasn’t the foggiest notion how a real newspaper is run, especially as it pertains to the relationship between reporters and editors.

In both books, Burr and his crusty old sports editor gnaw on each other about a dozen different things, which isn’t all that unusual. What is peculiar, however, is that an editor would allow his reporter--who also triples as a columnist, copy editor and photographer--to become the chief investigator for the police and then use his column space to provoke the killer into revealing himself. Maybe in Mayberry, R.F.D., but not in New York.

It also doesn’t help that, in two books, columnist Burr hasn’t written a paragraph that is remotely interesting to read. Jim Murray he ain’t.

In “Beanball,” the George Steinbrenner-like owner of the Brooklyn Bandits is killed by a 90-mile-per-hour fastball thrown at him while he is walking in a dark tunnel in his stadium. The suspects include the opposing World Series managers, a coach, a trainer, a couple of players and Burr himself.

When Burr isn’t busy playing detective, he must--get this--write a daily column, scribble additional sidebars, edit a women’s sports section, take photographs, defend himself against a sex-discrimination lawsuit, avoid hurled hardballs, practice gymnastics and keep his longtime girlfriend from throwing him out of their loft. Whew! I guess this explains how only Clark Kent could be Superman and a reporter at the same time.

Thank goodness the three-time Cy Young Award-winning Seaver was around to construct an entertaining World Series battle to distract the reader from all the other silliness. The games and players themselves are interesting, and the situations--while highly unlikely--are resolved with credibility and humor. Tarkenton similarly served Resnicow in “Murder at the Super Bowl.”

My favorite blunder in “Beanball” occurs every time Resnicow mentions that the Brooklyn “side of the stadium went wild.” If pressed, I’m sure Seaver would have told him that, in baseball, unlike high school football, a team’s fans occupy the whole stadium, with a handful of seats set aside for the opponent’s wives and executives.

A small point, perhaps, but--compounded by two dozen other, similar groaners--this annoyance made me want to throw the book on the ground and hit it with a Louisville Slugger.