If this isn't the year of the pitcher, it's got to be pretty close.

Strong arms have dominated the headlines, and theories about the cause of improved pitching are as plentiful as 100-mph fastballs, ranging from size to specialization to scouting to an expanding strike zone. After consulting with more than a dozen major league pitching experts, though, Sporting News settled on five primary reasons for the momentum on the mound.

1. A leveled playing field
In the five seasons before survey drug testing was implemented in 2003, there were 62 instances of a player reaching 40 homers in a season. In the next seven years, only 51. Last season, 39 homers led the American League. When Barry Bonds hit 73 homers in 2001, he had 39 at the All-Star break."The game definitely has been cleaned up," Rays pitching coach Jim Hickey says. "You're not seeing those gaudy numbers, those obscene numbers, you used to see."

"There could be a correlation to the new drug-testing policy," Cardinals general manager John Mozeliak says. "There has been an overall shift in baseball that is very defensive-minded. I also believe that pitchers are preparing more than ever for their starts."

Testing has downsized slugging and also boosted pitchers' confidence. "Maybe it has allowed them to do some things before that they weren't comfortable doing," Hickey says. "It's pretty hard to (keep your confidence up when you) throw a front-door breaking ball to a guy that even if he hits it off his fists, he hits it 380 feet down the line."

But not everyone is convinced drug testing is what has made the difference. "All that did was eliminate steroids," Mariners closer David Aardsma says. "There's a lot of other ways to get around that that can't be tested and are supposed to be better. Find a test for HGH and then we'll (really) see if things change."

2. Faster fastballs
A longtime scout was grousing recently about the hype that greeted Nationals phenom Stephen Strasburg before he had thrown his first major league pitch. "What's the big deal about 100 (mph)?" the scout asked. "I saw the Tigers and Royals recently, and Justin Verlander and Joel Zumaya hit 100 in the same game. The day before, Ryan Perry, Kyle Farnsworth and Robinson Tejeda were in the high 90s."

"You see it in the whole group of pitchers," says Curt Young, in his seventh season as A's pitching coach. "There has been an increase in velocity. More guys are in the 90s to mid-90s." This season, 19 starters are averaging 93 mph or better on their fastballs, according to fangraphs.com. That's up from six in 2005 and 14 in 2008. The increase from two seasons ago is even greater in the bullpen. Twenty relievers are averaging at least 95 mph this season, compared with eight in '05 and nine in '08.

"If you pull up (video of) pitchers from the '60s and watch them throw, it pales in comparison to what guys are doing now," Padres manager Bud Black says. "Teams have changed their scouting grades in the last decade with regards to velocity. What is an average fastball now used to be an above-average fastball. The 87 (mph) of 10 to 15 years back is like the 91 (mph) of today."

So where did this zip come from? "The evolution of the athlete," Black says.

3. Better early coaching
"This new generation is more prepared early on," Cardinals reliever Trever Miller says. "That's a testament to how early kids are starting to play the game and how well they're coached at a young age. When I was going to (youth) camps, it was all about hitting, hitting, hitting. This new generation is more about pitching."

This isn't to say the amateur ranks are churning out major league-ready pitchers. For every Mike Leake, the Reds right-hander who has a 2.92 ERA after bypassing the minors, there's an Adam Ottavino, the Cardinals righty who has endured the typical rookie struggles. But young pitchers today often arrive with more than wide eyes and a good fastball.

Astros minor league pitching coordinator Britt Burns, who started for the White Sox less than two months out of high school in 1978, sees the difference. "I threw hard, threw strikes, was left-handed and competed. I had all of that going for me," Burns says. "But I didn't have a breaking ball and had never heard of a changeup."

"They're ready to pitch more when they get up here," Hall of Fame pitcher and TBS analyst Dennis Eckersley says. "Everybody's got three or four pitches and knows something about how to pitch."

4. The Halladay Effect
If imitation is the highest form of flattery, the Phillies' Roy Halladay is the ace of adulation. Starters across the majors are copying his approach, which doesn't rely as much on blowing away hitters as carving them up with an assortment of nastiness. Hickey has coined a term for it: "Halladay-deification."

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"Don't get me wrong — Halladay has good stuff. He's just not crazy off the charts like (Ubaldo) Jimenez or Strasburg. He's pitching with what a lot of other people possess," Hickey says.

Because Halladay locates all of his pitches with precision, he can throw cutters that look like they will be balls but become strikes and two-seamers that look like they will be strikes but become balls. "In effect, he's taking a 17-inch plate and turning it into a 23-inch plate," Hickey says. "Hitters have a lot more to protect. Go back even a couple of years, there weren't a lot of other guys throwing front-door cutters, back door cutters, front-door two-seamers, backdoor two-seamers. Now you see 70 to 80 percent of the starters, maybe even more, doing it."

5. Better preparation
Gone are the days when pitchers used spring training to get in shape. Most report with six weeks of throwing behind them. Instead of devoting camp to getting their fastballs up to speed, they work on secondary pitches.

Because hitters typically need more time to adjust to soft stuff, pitchers start the season with an advantage. "For hitters, it used to be you'd come out of spring training and for the month of April, if you could hit a fastball, you were going to get a lot of hits because that's what the pitcher had the best command of," Cardinals pitching coach Dave Duncan says. "But now, right from the get-go, you're seeing more pitchers better equipped to utilize their secondary pitches."

In the no-hitter he threw in June, hard-throwing Diamondbacks right-hander Edwin Jackson didn't have to lean on his fastball. "Being able to throw my slider for strikes in any count saved me," Jackson says.

Down the stretch, though, that might not be as much of an advantage. "As you get deeper in the season and hitters start to catch up, that's when you start evaluating if pitching is controlling the hitting or not," Duncan says.

In other words, don't give pitchers too much adulation yet. But give them the first half of 2010. They deserve that much after surviving the era of offense.

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