Yankees pitcher Masahiro Tanaka delivers a pitch during the first...

Yankees pitcher Masahiro Tanaka delivers a pitch during the first inning of a game against the Minnesota Twins on Thursday, July 3, 2014, in Minneapolis. Credit: AP / Jim Mone

With so much time and energy invested in Japanese pitchers having to adapt to the five-man rotation used in the States, how about if we posed the opposite scenario.

Would it make more sense if Major League Baseball was the one that changed instead?

Maybe NBP (Nippon Professional Baseball), with its six-man rotations allowing for additional rest, is the better model for keeping pitchers healthy over the course of a six-month season.

And if that sounds too radical, the question you then have to ask is this: What makes five starters right and six wrong? Or three? Or four?

That debate has been going on since the sport was invented, but it again has become timely this season because of the stunning rate of pitchers lost to Tommy John surgery during the past year or so.

Masahiro Tanaka was 13 weeks into his major-league transition, a mere 18 starts, before suffering a partial tear of the ulnar collateral ligament in his right elbow. Was it a byproduct of adjusting to a new pitching schedule? Was it the cumulative effect of stacking up 1,315 innings for the Rakuten Golden Eagles?

That might be impossible to pinpoint. But a previous career in Japan is not what felled the likes of Matt Harvey, Jose Fernandez, Ivan Nova or Bronson Arroyo, just to name a few.

One pitcher qualified to know what Tanaka is experiencing, however, is Daisuke Matsuzaka, who needed Tommy John surgery himself in 2011, midway through his fifth season in the majors, at age 30.

Matsuzaka blamed a career's worth of stress on the elbow, partly because of mechanics but also a heavy workload. Like Tanaka, he had to get used to the five-man rotation -- and he quickly noticed the strain of pitching more than once a week.

"I think the six-man rotation is physically easier simply because of that extra day of rest," Matsuzaka said through an interpreter. "But having that extra day also allows you to pitch more [in that start], to have a larger pitch count than you do over here, because you're more rested."

That's the tradeoff. Employing a six-man rotation means fewer starts to spread around, and the NPB regular season is only 144 games. For Matsuzaka, that bumped him down to 23.8 starts per season, but each averaged 7 1/3 innings. In his first two seasons with the Red Sox, he made 32 and 29 starts, respectively, at an average length of six innings.

Matsuzaka has never been very economical, and his skyrocketing pitch counts -- which became legendary in Japan -- led to the earlier exits here. While that was accepted by the Seibu Lions because Matsuzaka took the mound only once a week, major-league managers start getting antsy as soon as a pitch count cracks 90. It's all about preservation with a five-man rotation, and that often trumps performance.

"It's very physically demanding," Matsuzaka said. "But that's probably why there's such a large value placed on pitch counts over here."

Under the NPB's guidelines, teams have a 28-man roster, but only 25 players are active on a given day -- with three of the pitchers basically excused from that game. Days off are fairly standard, too, with one a week.

Compare that to what the Yankees are currently enduring, with 17 consecutive games heading into the All-Star break. That can be torturous for a pitching staff and forces teams to employ a Triple-A shuttle to rotate in fresh arms on occasion.

Braves pitching coach Roger McDowell was a 12-year veteran who logged 1,050 innings with five different teams. Since 2006, he's presided over one of the game's better staffs in Atlanta, and McDowell doesn't see any particularly damaging trends at the major-league level.

Sure, the schedule can be exhausting, but McDowell believes that piloting a rotation is a fluid operation and must be done on an individual basis during six months -- or seven, including playoffs.

"Sometimes, if there are two off days, guys are pitching a week between starts," McDowell said. "Does it help? I don't know. I couldn't give you an answer. There's so many variables. Whether it's travel, whether it's workload, high-stress innings.

"And what are those high-stress innings? Is it 15 pitches? Is it 20 pitches? It can be different for everyone.

"Same thing for pitch count. There are some guys who at 90 pitches -- physically and mentally -- they're done. Does it make sense? I don't know that I'm that smart."

McDowell, who made his debut in 1985 with the Mets, isn't so sure that pitching injuries are any more rampant now than they were back then.

The number of Tommy John surgeries appears elevated, and the Braves lost their share this season in Brandon Beachy and Kris Medlen. But McDowell said there always have been shoulder problems and other non-elbow issues to consider.

"I think medicine has gotten better," McDowell said. "I think our ability to fix people has gotten better. When I first came up, we weren't getting MRIs. Technology has definitely helped in prolonging careers. But it's also helped in defining more injuries."

It's a valid argument. Are elbow ligament tears easier to find and diagnose now than they were two decades ago? And would players be as eager to get Tommy John surgery back then for smaller tears if they had been discovered?

In talking about six-man rotations with Matsuzaka, and if that schedule is the reason there seems to be fewer Tommy John surgeries performed on NPB pitchers, he did believe it could be a factor in preventing injury.

But Matsuzaka brought up another point, too. It's not that Japanese pitchers weren't getting hurt. They just didn't opt for the surgery.

"In Japan, a lot of people were against the idea of Tommy John," Matsuzaka said. "It was just a little too foreign. But it's recently become a lot more accepted and you see it occurring more.

"The other difference is that in the U.S., you see pitchers getting Tommy John even without a full tear -- just a partial tear. In Japan, in general, you don't see that unless it's a full tear. They'll pitch through it and try to recover their arm through rehab."

That's what Tanaka plans to do for now. As for the future of pitching rotations -- and they might evolve to respond to this recent Tommy John crisis -- there doesn't seem to be one solution.

In the case of a six-man rotation, does a more rested pitcher -- one who presumably can go deeper into games with that extra day -- sound like an upgrade for the modern game?

McDowell pretty much summed it up when he said, "Depends on how good those six are."