In today's game, most pitchers are lame ducks at the plate, often an automatic out waiting to happen.
Zambrano might carry the best bat of any current pitcher. The three-time Silver Slugger Award recipient launched his 24th career round-tripper in a victory on June 3. He's hit at least one home run in each of the past 10 seasons.
"As a pitcher in the National League, you have to be able to run, bunt, hit," said Zambrano, who belted a career-high six homers in 2006. "I take that seriously. I take pride in what I do. Every time I'm on the mound, I feel like a pitcher. But when I'm in the box, I feel like a hitter. I take everything seriously."
For most Major League pitchers, that mantra isn't so easy to follow. In the NL, it's part of the job description -- though basically buried in the fine print. For American Leaguers and the overwhelming majority of NL pitchers who weren't blessed with Zambrano's raw power, hitting is just an additional task that takes away from their focus atop the hill.
"Every time you have to swing the bat or run the bases or worry about the signs, you get tired mentally and physically," said Indians right-hander Ubaldo Jimenez, who spent 5 1/2 years in the NL with Colorado.
AL squads have pitchers take batting practice only in preparation for Interleague Play, so they carry the extra burden just a few weeks out of the season. Senior Circuit hurlers have to hit regularly.
"In Spring Training, when I was with the Mets, every other day, we would hit," said Tribe reliever Joe Smith. "If you're not pitching, you're hitting."
Some pitchers are just naturals at the plate.
Cleveland righty Josh Tomlin totes a career average of .571, with four hits in seven trips to the dish. He entered the 2012 campaign a perfect 2-for-2 in his career. So when Indians pitchers first started taking batting practice in mid-May as Interleague Play approached, Tomlin's teammates followed his lead.
Center fielder Michael Brantley walked away unimpressed when the "Little Cowboy" didn't bring his A-game to the rodeo. Tomlin said his longest drive fell short of the outfielders.
"I swing a wet newspaper," the 27-year-old pitcher said.
Nevertheless, Tomlin has been the toughest out among Tribe hurlers. He played shortstop for two years in junior college, so hitting isn't a foreign subject to him.
"I don't give hitting pointers," Tomlin said. "I just tell them, 'Just close your eyes and swing.' That's what I do."
Before his first encounter with Interleague Play, Angels righty Jered Weaver hadn't dug his cleats into a batter's box since his junior year of high school.
"It's like riding a bike," Weaver said, laughing. "No, it's tough. In high school, you're facing guys that are throwing 85 mph. In the big leagues, guys are throwing 95 mph. It's a little different."
Wes Ferrell holds the all-time record for home runs by a pitcher in the modern era, with 38. Zambrano's 24 blasts trump the totals of his current colleagues. Brewers hurlers Livan Hernandez and Yovani Gallardo have 10 and nine, respectively. Padres pitcher Micah Owings holds a career .283 average with nine homers in 205 at-bats. In his rookie season with Arizona in 2007, he recorded 12 extra-base hits (20 hits total) in 60 at-bats.
"You can take batting practice all you want," said Cleveland sinkerballer Derek Lowe, who spent seven seasons in the NL before being traded to the Tribe over the winter. "But to be able to bring that type of power to the plate as a pitcher is pretty impressive."
Zambrano certainly does. The Marlins entered Friday's action batting .243 as a team. "Big Z" has a career average of .238.
"The Lord gave me the ability to hit," Zambrano said. "I'm not a small man. I'm a big man. If I hit the ball good, it will travel far."
For every Zambrano, though, there are hordes of guys like Cardinals righty Chris Carpenter, who has a career average of .118 in 433 at-bats over 14 seasons. In a 14-year career split between four clubs, Brian Moehler, who last pitched in 2010, tallied nine hits in 202 at-bats (.045 average).
"The bottom line is, it's hard to hit," said Lowe, who has one homer in 436 career at-bats. "We all think we can hit because we hit in high school or college, but this is a whole different level. I think there's an advantage if you grew up playing a different position as opposed to if you've never done it before. Then, you're probably not going to have much of a chance."
One thing is certain: There's usually no one an opposing pitcher would rather see stroll into the batter's box than one of their own.
"I always like facing other pitchers," Lowe said. "That's where I get all my strikeouts."