Best free agent: Big Unit

Randy Johnson and Barry Bonds would not seem to have much in common, aside from their inevitable elections to the Hall of Fame.

Yet, they are linked in another way as well.

They rank as the two best free-agent signings ever – no debate.

Signed by the San Francisco Giants for six years and $43.75 million in 1993 and now in the third year of a five-year, $90-million contract, Bonds does not need another home run to legitimize those agreements.

Similarly, there’s no need for Johnson to pitch another perfect game to justify the four-year, $54-million contract he received from the Arizona Diamondbacks in 1999 or his $8-million option in ‘03 or the two-year, $32-million extension he is starting this year.

Or is it every week that a 40-year-old pitcher attempts to match Johnny Vander Meer by throwing a no-hitter in consecutive starts, which is what Johnson will try to do today when he faces Florida’s Dontrelle Willis?

Then again, that perfect game Tuesday, with Johnson pumping 95-mph heaters past the bewildered Atlanta Braves, merely provided another sentence for his Cooperstown plaque and enhanced a litany of impressive accomplishments since the Big Unit opted for Paradise Valley over similar free-agent offers from the Angels and Dodgers – the latter promptly swallowing their disappointment by spending twice as much on Kevin Brown.

“It’s interesting,” said Jerry Colangelo, the managing general partner of the Diamondbacks. “Someone called and asked what (the perfect game) does for Randy historically. Is he the best left-hander of all time, second-best, third-best?

“The way I see it is that his five Cy Young Awards, his two no-hitters, his perfect game, all of this just means he’s one of the top three of all time and it doesn’t matter if he’s one, two or three in my opinion. As it relates to free-agent signings, it also doesn’t matter whether he or Bonds is one or two.

“You’re talking about two of the most extraordinary free-agent signings, and maybe it’s a tie.

“I mean, there are times you sign players and don’t get anything close to a return. In this case, Randy Johnson has come through in spades. Everything we could have hoped for we got and more. It’s been an incredible run – and even more amazing when you consider it’s come relatively late in his life as a pro athlete.”

Although Johnson, Bonds and Roger Clemens are redefining “late,” Johnson has definitely had an incredible run with the Diamondbacks.

He won four Cy Young Awards in a row before his knee problems of last year, going 81-27 in the four seasons while leading the National League in strikeouts each year, twice leading the league in earned-run average while never going over 2.64 in the four years and never pitching fewer than 248 2/3 innings. He also was co-MVP of the 2001 World Series.

In the often treacherous business of free-agent investments, Johnson and Bonds stand alone, but others have returned significant dividends in various forms. A short list of the best would include:

Reggie Jackson by the New York Yankees in 1977; Goose Gossage by the Yankees in 1978; Pete Rose by the Philadelphia Phillies in 1979; Nolan Ryan by the Houston Astros in 1980 and the Texas Rangers in 1989; Kirk Gibson by the Dodgers in 1988; Jack Morris by the Minnesota Twins in 1991; Greg Maddux by Atlanta in 1993; Roger Clemens by the Toronto Blue Jays in 1996 and the Astros in 2004; Alex Rodriguez (outrageous contract but game’s best stats in return) by Texas in 2001; and Ivan Rodriguez by Florida in 2003.