ST. LOUIS — The hottest-hitting duo in baseball has shown no signs of cooling off through the first three-plus weeks of the season.

Left fielder Matt Holliday and third baseman Matt Carpenter are the only teammates batting at least .360 — Holliday is at .383, Carpenter .380 — putting them both among the top five in Major League Baseball. Both have reached base in all 19 games — with the exception of one off day for Holliday — and put together 12-game hit streaks.

"It’s fun to watch," says cleanup hitter Matt Adams, who gets multiple chances to drive home Holliday or Carpenter virtually every game. "It feels like whenever Carp hits the ball he’s always on second or third, so it’s nice having those guys a lot of the time in scoring position."

Carpenter has gotten more attention, thanks to 12 multi-hit games in his last 15 — a stretch during which he has all of his major league-best 12 doubles — and 14 multi-hit games overall. His 12 doubles are tied for second most in the first 19 games of a season in MLB history. If not for the expansive outfield of Busch Stadium, Carpenter would have fewer doubles and more than his team-best three home runs.

Holliday hit his first home run of the season Saturday night, a three-run jack in the seventh inning that provided the winning runs in a 5-3 triumph over Milwaukee and counts as one of the Cardinals’ biggest hits this season. But despite only three extra-base hits, the left fielder Fangraphs called "The Game’s Most Underrated Star" earlier this month leads the majors with an incredible .500 on-base percentage, thanks in part to a team-high 14 walks.

He hit an RBI double to left-center in the first inning to put St. Louis on the board in Tuesday’s 11-5 win over Milwaukee. Later, he demonstrated his ability to hit the ball to all fields with a single to right to cap off a 3-for-4 night.

"He’s just got a real nice stroke working," manager Mike Matheny says. "It’s dangerous how hard he hits the ball back up the middle, too. The double that he hits in the pull gap, he’s just in a good spot and needs to stay there."

Holliday and Carpenter have been even better in key situations. Both are batting .600 with runners in scoring position and share the team lead with 12 RBIs, and Holliday’s success is a major reason Carpenter is tied for fourth in the league with 17 runs scored.

The Cardinals’ new batting order brings the duo up in consecutive at-bats, a formula that worked brilliantly Tuesday night. Philadelphia retired both players only once in five tries as Carpenter and Holliday contributed to four of St. Louis’ five multi-run innings.

You can follow Luke Thompson on Twitter at @FS_LukeT or email him at lukegthompson87@gmail.com.