"It would have been nice to get a scoreless inning, but we won and we both (Nathan and Johan Santana) got in the game, so you really can't complain," Nathan said. "This is something I won't forget."
Nathan induced Houston's Morgan Ensberg to pop up to first for the first out of the inning before giving up Alou's double to left. Alou went to third when Cincinnati's Felipe Lopez singled to center.
Florida's Miguel Cabrera then hit into a forceout, scoring Alou, before Nathan retired Luis Castillo of the Marlins to end the eighth inning.
"Both teams really had a lot of great hitters," Nathan said. "You really had to be on, there's no room for error with these lineups. I think it helped us a lot to get the lead early and to keep adding on."
Nathan's teammate, Santana, ran into some trouble of his own but escaped without allowing any runs.
The Major League strikeout leader and reigning AL Cy Young Award winner came in to pitch the fourth with the AL leading, 3-0.
Santana got off to a shaky start when he gave up a double to Derrek Lee of the Cubs, followed by a walk to Jim Edmonds of St. Louis. But the left-hander kept the shutout intact when he coaxed a double-play ball from Aramis Ramirez and retired Mike Piazza of the Mets on a grounder to second.
Santana had left by the time the AL clubhouse was opened to the media following the game, and was not available for comment.
"We're both glad to be here and happy we got in the game," Nathan said. "And happy we didn't let [our teammates] down."
Jim Molony is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.