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Roy Oswalt has won each of his past three decisions and not lost a game since June 19.

By Fernando Vina, ESPN

It seems like every year we forget about how much of a push the Houston Astros make in the second half. They looked like a completely clueless team at the end of May, when the Astros were 20-29 and 9½ games back in the NL Central. They were completely off everyone's radar. We should have known a run was coming, given that Houston's average record after the break in the past five seasons is 42-31. And the run has come -- the Astros have trimmed that 9½-game deficit all the way down to one game. This team doesn't stop battling, yet it hasn't played in October since its 2005 World Series run.

You look at the NL Central this year and certainly no one is running away with it. The Cubs, despite putting an end to the Phillies' 10-game winning streak with a win Wednesday, haven't been nearly the same team they were a year ago. The Cardinals haven't been able to create any real separation from the rest of the pack. The Astros have fought their way to a 49-46 record and are now legitimate contenders. It all starts with their ace, Roy Oswalt.

In his career, Oswalt has been impressive in the second half, posting a 68-20 record after the All-Star break. He's a hard thrower with great durability, a guy built to keep you in games. And that's exactly what he did Wednesday, locking in a duel with St. Louis' Chris Carpenter. He kept the Astros in the game, and Houston came to post a 4-3 win. Sure, Oswalt got a no-decision, but he kept his team within striking distance, and when you have that type of guy to anchor your rotation, the chances of winning every five days are tremendous.

Wandy Rodriguez gives you that shot, as well. He's 10-6 with a 2.72 ERA and has added yet another dimension to this ballclub's rotation.

The Astros have an advantage over the other teams competing in that division; they have a prolific leadoff man. Michael Bourn, who came to Houston in the Brad Lidge trade, quickly is becoming one of the game's most enticing players. He has a .354 OBP and is leading the National League in stolen bases (35) and triples (8). His presence on the bases gives RBI men Miguel Tejada, Carlos Lee and Lance Berkman chances to put up big offensive numbers. We've seen guys such as Jose Reyes and Jimmy Rollins bring a jolt to teams; it's without question that Bourn can do the same for Houston.

We've seen the Killer B's in Houston, but imagine if they had Killer Roys in the front of their rotation? If Drayton McLane and Ed Wade are looking for a boost, they need to involve themselves in the Roy Halladay sweepstakes. Having the righty Roys pitch on back-to-back days will guarantee you at least one win, if not two. Add in Rodriguez and Brian Moehler, and things are looking pretty good. Houston does have a history of trading for an ace at the deadline. Randy Johnson was brought in as a rental in 1998. Even if a team such as the Phillies lands Halladay, there is always a chance to get into talks with the Indians for Cliff Lee. If McLane is willing to take the chance on either guy, it certainly would be worth it.

Unless the Astros can make a trade, their chances for October are slim. They will continue to push along like they always do. Their middle-of-the-order hitters (Berkman, Lee, Tejada) are among the best in baseball. Then you add in veterans such as Ivan Rodriguez and Darin Erstad, and scrappy youngsters Hunter Pence and Bourn, and this team was bound to get hot any minute.

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HALL OF FAME BY THE NUMBERS: NO. 19

Editor's Note: This week, leading up to the Hall of Fame induction ceremony Sunday in Cooperstown, N.Y., Baseball Tonight is highlighting the five greatest uniform numbers in baseball history, based on the players (both Hall of Famers and future Hall of Famers) who have worn them, and debating which player was the best ever to don that number.

By Tim Kurkjian, ESPN

Two of the best No. 19s in baseball history were already great major leaguers by age 19. By the end of their careers, all our 19s were great, creating a great debate for the best 19.

Bob Feller leads the way. He pitched in the big leagues as a 17-year-old and is the only pitcher to have 18 strikeouts in a game when he was 18 years old. Feller won 266 games. He won 20 six times, led his league in strikeouts seven times and threw three no-hitters, including one on Opening Day in 1940. Had he not lost four prime years when he enlisted in the Navy at 23 to fight in the Pacific, Feller might have won another 100 games.

Robin Yount made his major league debut as an 18-year-old shortstop and, by age 25, he had 1,000 hits. He finished with 3,142 hits, is the only player in history to win an MVP award as an infielder and as an outfielder and is the last Brewer to win a Gold Glove -- and that was 27 years ago.

The Greatest No. 19

Who was the greatest player to wear No. 19 in baseball history? • Bob Feller • Tony Gwynn • Fred McGriff • Billy Pierce • Robin Yount Register your vote

Tony Gwynn's .338 average is the 17th-highest of all time; he and Ted Williams are the only players with averages that high to play after 1938. Gwynn won eight batting titles -- only Ty Cobb had more -- he stole 319 bases and won five Gold Gloves. For a five-year period, Gwynn hit .337 with two strikes; no player in that time hit that high using all his strikes.

Fred McGriff hit 493 home runs and, over a 15-year period, averaged 31 homers, 97 RBIs and a .288 batting average -- only 10 other players in history have done that, and they're either in the Hall of Fame or will be someday. Some say Billy Pierce should be in the Hall with 211 wins and a 3.27 ERA, but he is pushed for the last No. 19 by Dave Righetti and someday Josh Beckett.

Hey, 19, you're good.