PHOENIX — When the Arizona Diamondbacks look across the field at the Colorado Rockies this week, they may feel as if they're looking into a mirror.

The teams took similar routes to an unlikely destination — the NL championship series.

"We're going to have our hands full with Arizona, a tough team," Rockies outfielder Jeff Baker said. "We know them. They know us."

Start with their records: Arizona won the NL West with a league-best 90-72. The Rockies, who had to defeat San Diego in a one-game playoff to earn a wild card berth, finished 90-73.

Both clubs have built from within, and they've done it relatively cheaply. The Rockies entered the season with a payroll of $54.4 million, $2.4 million more than the Diamondbacks. Only four clubs had lower payrolls.

Instead of spending on free agents, both organizations committed to building through the draft. Two of their finest products can be found at shortstop — Colorado's Troy Tulowitzki, drafted in the first round two years ago, and Arizona's Stephen Drew, picked in the first round a year earlier.

Game 1 on Thursday night will pit dazzling starting pitchers Brandon Webb of Arizona and Jeff Francis of Colorado. Both are homegrown.

"It speaks to the good old-fashioned values of baseball: scouting and player development and building from within and being patient and taking chances and things working out," Colorado manager Clint Hurdle said after the Rockies wrapped up a three-game sweep of the Philadelphia Phillies in their NL playoff series.

Inexperience can prove costly. But for the Diamondbacks and the Rockies, what they don't know hasn't hurt them.

"With this team, everybody calls us young, but I think it's the most exciting team I've been on," said Drew, the younger brother of Boston's J.D. Drew.

The playoffs have been sweet for two teams that have struggled in recent years.

Colorado, which lost 94 games in 2004 and 95 in 2005, posted its first winning record since 2000. The Diamondbacks went 51-111 three years ago, and this year they broke a streak of three consecutive losing seasons, longest in the franchise's 10 years.

Both started slowly this year; the Diamondbacks were 47-43 at the All-Star break, third in the NL West, 3 1/2 games behind San Diego. Colorado was 44-44 and in fourth place, 5 1/2 games out.

"Everybody has been waiting for them to fall on their faces, but they're a good team," Colorado reliever Brian Fuentes said of the Diamondbacks. "No one projected us to be where we are, so it's going to be two very good ball clubs going at it."

Instead of quitting, both teams kept playing hard. That's a credit to Hurdle and Arizona manager Bob Melvin, as well as the desire of younger players to stick in the major leagues.

"It's a team," said Arizona left fielder Eric Byrnes, one of the Diamondbacks' few veterans. "It's as much of a team as you'll find in professional sports today.

"You have 25 guys pulling for each other," Byrnes said. "I've never heard one guy complain all year. We have guys who are ready to win. We've already exceeded expectation so far and we're going to continue to do so."

The Diamondbacks and Rockies have shown a penchant for hot streaks. The Diamondbacks won 17 of 20 in July and August, taking over first place.

The Rockies have won 17 of their last 18, the hottest streak in their 15-year history.

The only pitcher to defeat the Rockies in that stretch? Webb, who beat Francis 4-2 on Sept. 28 in Denver.

Said Colorado outfielder Brad Hawpe, "I looked at the date the other day and I don't even know what the date is now. Things are flying by now."

The Diamondbacks and Rockies met four times in spring training — their camps are a few miles apart in Tucson — and 18 in the regular season, with the Rockies winning the season series 10-8.

"From both sides, there's going to be no surprises," Hurdle said. "It's going to be who plays the best, and that's what baseball should be about."

The similarities between Arizona and Colorado have showed in the playoffs. Arizona outscored the Chicago Cubs 16-6 in a three-game sweep of their series. The Rockies swept the Phillies by a combined score of 16-8.

In both series, the Diamondbacks and Rockies got timely hitting while shutting down their opponents' top batters.

Against Colorado, Philadelphia's Ryan Howard and Jimmy Rollins went a combined 5-for-23 (.217) with 2 homers and 5 RBIs.

The Diamondbacks limited Cubs sluggers Alfonso Soriano, Derrek Lee and Aramis Ramirez to a combined 9-for-36 (.250) with no home runs or RBIs.

"A lot of people, they're not giving credit to those guys because they're young and they don't have the big names on their team," Soriano said of Arizona's pitchers. "But they play the game good. You have to give them a lot of credit."