Houston was a baseball city again Sunday.

It only lasted for one brief, buzzing night. Fifty-one years of Astros history, tradition and reinvention squeezed into just three hours as the longtime National League team made its American League debut against the intrastate-rival Rangers before 41,307 at Minute Maid Park.

But the often-ridiculed Astros were Major League Baseball’s first heartbeat of the 2013 season. And as they opened with an 8-2 victory, a rebuilding club with its MLB-low $20 million active payroll received a one-night reprieve from 100-plus-loss predictions and “who are these guys?” punch lines.

The Astros mattered Sunday. With Texans defensive end J.J. Watt throwing out the ceremonial first pitch and Astros starter Bud Norris recording the team’s first AL pitch — a 94-mph fastball for a strike at 7:08 p.m. — Minute Maid again was filled with flashing cameras and cheering fans.

A hard single to left field by leadoff hitter Jose Altuve off Rangers righthander Matt Harrison followed in the first inning, and the Astros were off and running with new uniforms, new logos, new image, new slogan, new players and big, new ideas for a new league.

Leading the charge was Bo Porter.

When the first-year manager sprinted out of the first-base dugout in the bottom of the first inning, racing toward second to question what TV replays appeared to show was a blown call, the Astros had their first breath of real, new life in years.

Porter didn’t walk, stroll or jog. He flat out ran. Then he briefly spoke with second-base umpire Andy Fletcher, who called Altuve out on an attempted steal. Porter then raced back to the Astros’ dugout, allowing a team already counted out by almost every baseball expert in the game to return to its season-long underdog fight.

Porter preached aggressiveness, sacrifice and personal willpower throughout seven weeks of spring training. As he strove to unite his mix-and-match team of unknown young players and low-cost veterans, Porter ended up becoming the best story on an anonymous club.