The rules have changed. There is a new trickle-down theory at play in South Florida sports. Call it The Heat Effect.

Seldom has there been much cross-pollinating among our four major professional teams, each operating as separate ships at sea beholden to distinct fan bases. Now, though, because one of our teams and only one is so prominent, popular and successful, the onus is on the other three to respond simply to maintain (let alone grow) their diminished place in this market.

The result we are beginning to see is the Marlins, Dolphins and Panthers conveying more urgency, more boldness, more of a nod to public relations, and generally more of a win-now mind-set. The word rebuilding has been struck from the local vocabulary; or if it remains it is an expletive now.

Miami’s NBA championship parade still echoes but even now our state-of-the-art franchise aims to turn up the Heat, not only on the rest of the league but also in this market. You do not stand pat. Not when you see the Los Angeles Lakers acquiring Steve Nash, and the Brooklyn Nets wooing Dwight Howard. So the Heat casts in free agency for former Celtics guard Ray Allen, who visited to be wooed Thursday.

Allen turns 37 this month. Doesn’t matter. They see his three-point shots spreading the floor and opening space near the basket for the Big 3 to attack. Besides, the Heat endeavors to add a key piece not with five years from now in mind, but with next season’s playoffs in mind. With another parade in mind.

Unlike most other bidders, Miami can offer Allen neither the most money nor a starting role, yet is judged a strong candidate to sign him for some of the same reasons other local teams are scrambling to keep up:

What owner Micky Arison and architect Pat Riley have fashioned here, led by reigning league MVP LeBron James and Dwyane Wade, has a chance to become a basketball dynasty and grand-marshal this region’s sports parade for years.

So you look around and you begin to see the impact.

The Heat Effect:

Do you think it’s a coincidence the Marlins agreed to star on Showtime’s The Franchise reality series this summer?

Even a new ballpark, new spending and new stars such as shortstop Jose Reyes and manager Ozzie Guillen couldn’t hoist the Marlins above the star-dominated, title-bound Heat this spring-into-summer.

Now, languishing a disappointing fourth place in the National League East and struggling to score runs, the Marlins trade two prospects to Houston for immediate offensive help in first baseman Carlos Lee, a proven run producer. Immediate? He doubled, singled and scored in his debut Thursday, a win.

The old Marlins would not have dealt pieces of the future for a beefed-up present, certainly not while in fourth place. The old Marlins would not have seen Lee, 36, as a wise investment. But age is not nearly as big a factor when you’re thinking “right now,” not toward some vague and distant tomorrow.

Now, with a new ballpark and a Heat championship parade winding raucously through their city, glomming the spotlight, the Marlins see an urgency they never seemed to in the past — an urgency only magnified by baseball adding an extra wild-card team and reducing excuses for not making the playoffs. The new rules are that the Marlins know it will take the postseason to compete for the marquee in this market now.