Why does the National League strike out in interleague play?

Same rules, yes.

Even playing field? Not so much. Just because National and American league teams either both use a designated hitter or let their pitchers hit in interleague play doesn’t mean that they are on equal footing.

NL teams who play in AL parks often must contend with a feared designated hitter such as David Ortiz or Vladimir Guerrero.

The challenge isn’t always so daunting for the AL teams in those contests. They largely face DHs drawn from utility players and journeymen who otherwise wouldn’t crack the lineup. We’re talking Jay Gibbons or Wily Mo Pena here.

“The NL guys are not used to the DH,” said Angels Manager Mike Scioscia, whose team’s sustained success against NL teams has helped the AL compile a winning record during interleague play in 11 of the 15 years since its debut in 1997.

“When you look at the benches in the NL and compare them with the DHs in the AL, I don’t think the NL is putting a hitter into the lineup who quite makes up for what some AL DHs bring to their teams.”

That short-handed feeling has extended to home games for many NL teams. Sending Hiroki Kuroda and Doug Davis to the plate doesn’t exactly make opposing pitchers quiver in their cleats, even though NL pitchers are usually more seasoned hitters than their AL counterparts.

“The pitchers are pitchers,” said Dodgers catcher Rod Barajas, who has extensive experience in both leagues. “They’re usually not going to do much at the plate, so that doesn’t really help us out much in the National League.”

Indeed, it hasn’t. The NL has lost every season series since 2003, compiling a 1,708-1,874 record all-time. The AL has prevailed in 52.3% of interleague games, including a 66-56 mark in 2011 through Wednesday.

Its dominance is even more pronounced at home, where it has won 57.8% of games against NL opponents.

“It’s tough for the NL teams coming to the AL parks,” said Angels pitcher Dan Haren, who will start the opener of the Freeway Series against the Dodgers on Friday at Dodger Stadium. “They don’t have the DH; they have a hitter to plug in, but it’s not necessarily a guy they build their lineup around. I’m not surprised it’s gone the way it has.”

The Dodgers have routinely been on the losing end in interleague play, going 106-124. They have failed to produce a winning record against AL teams in any season since going 10-8 in 2004.

Their struggles have been particularly acute against the Angels. The Dodgers lost five of six games against their Southland rivals last year and have dropped eight of their last 11 games against the Angels at Dodger Stadium.

Of course, they’re not the only NL team bedeviled by the Angels, whose interleague record of 125-82 since 2000 is the best in baseball. The Angels also have a baseball-best 74-56 road record since interleague play started.

“They play a National League-style game,” Dodgers Manager Don Mattingly said. “They’re tough because they’ve got a lot of guys who can run and can do multiple things. They’ll steal on you, they bunt, they hit and run.”

Another factor that has bolstered the Angels’ success in NL parks is that they don’t typically feature a middle-of-the-order slugger who has been exclusively a designated hitter. They usually rotate the DH spot among several players, allowing them to insert their DH into the field when they play in NL parks.

That’s not always the case among AL teams. Boston’s Ortiz is expected to make only a handful of starts when the Red Sox play nine consecutive games at NL parks starting Friday in Pittsburgh.

Detroit Manager Jim Leyland, who used primary designated hitter Victor Martinez at catcher and at first base against the Dodgers earlier this week to keep his bat in the lineup, predicted that Boston counterpart Terry Francona would also get creative with his lineup.

“I was telling one of my coaches, I bet maybe they’ll try to figure out a way to put [first baseman Adrian] Gonzalez in the outfield for a couple of days so Ortiz can play,” said Leyland, who is in favor of both leagues either adopting or abolishing the DH for consistency’s sake.

NL teams can also juggle their lineups to put a potent bat at DH. But in those instances, they usually must pull someone off the bench to replace those players in the field.

When the Dodgers inserted Matt Kemp at DH in May against the Chicago White Sox, they had few options except using the light-hitting Tony Gwynn Jr. in Kemp’s spot in center field.

“A National League team goes into an AL park, it’s really an extra player that serves as your DH,” Dodgers General Manager Ned Colletti said. “You don’t have the typical DH-type player who maybe is limited defensively but can run 30 out of the yard.”

That became abundantly clear during one stretch from 2005 through 2007 in which the Dodgers dropped 20 of 21 interleague road games. Their designated hitters batted .177 during that span as opposed to a .293 average for their AL opponents.

Some analysts contend that the AL’s dominance in interleague play is a result of moneyed ball; this season, the league has four of the top five team payrolls in baseball. But Haren pointed out that financial backing doesn’t guarantee success, noting that two of the bigger spenders in the NL -- the New York Mets and Chicago Cubs -- haven’t contended in recent years.

Could the AL simply be the better league? Since interleague play began, it has won eight of 14 World Series and 12 of 14 All-Star games (with one tie).

Colletti dismissed that opinion, noting that All-Star results are based on which league prevailed on a given day and that the NL is only one victory removed from a push in World Series results since interleague play started.

Dodgers third baseman Casey Blake, who spent parts of 10 seasons in the AL, said the discrepancy in interleague success might be attributable to a difference in philosophy: AL teams are built around offense while NL teams are centered on pitching.

“They say good pitching beats good hitting,” Blake said, “but it doesn’t seem so in this case.”

Times staff writer Mike DiGiovanna contributed to this report.

ben.bolch@latimes.com