Revenge of the Day 4 starters

Earlier this month, Mike Cuellar of the Baltimore Orioles died of cancer at the age of 72. Cuellar won the AL Cy Young Award in 1969, sharing the honors with Denny McLain of the Detroit Tigers. However, that wasn't Cuellar's claim to fame. No, what most people think of when they hear his name is his being part of what was possibly the greatest pitching rotation of all time.

In 1971, all four Baltimore starters won at least 20 games. Cuellar, Dave McNally, Jim Palmer and Pat Dobson together accomplished a feat that has not been matched since. In total, 14 different major league pitchers reached the 20-win milestone that season. To put that into perspective, since 2004, only 11 different pitchers have won 20 games in a season (Roy Oswalt did it twice) and in both 2006 and 2009, nobody managed to do it at all.

Certainly, the game has changed plenty over the past four decades. Pitchers are no longer expected to finish what they start. In fact, we are usually shocked when we do witness a complete game. But the biggest perceived difference between pitching now and then isn't at the front of the rotation; rather, it's at the back end of things. With six more teams around today than in Cuellar's time, and all of them utilizing five-man rotations as opposed to four, collective wisdom says there simply isn't enough talent to go around.

In short, you would be right to assume starting pitching has slowly but surely spread itself way too thin. In fact, when compiling Daily Notes for this past Thursday, and ranking the day's scheduled starters, it was striking; Here we were, only the fourth full day of games of the season, with most teams still reaching only three deep into their rotation, and already the talent level of those names seemed a bit, well, unimpressive. C.J. Wilson, Justin Masterson, Doug Fister, Craig Stammen, Nate Robertson and Jonathon Niese? You mean there are still guys behind them in their respective rotations?

Are things really that bad?

I decided to do a little "unscientific" research. I went back and tracked down the names of the starters on the fourth full day of games for selected seasons over the years, and calculated the average of their collective stats for those seasons. I wanted to see if indeed the quality of the "Day 4" guys, as I took to calling them, was indeed getting worse and worse as the decades flew by. As it turns out, the stats seemed to match up with my expectations:

"Day 4" starters at the start of past four decades

The expected win-loss total among this tier of pitchers has steadily gotten worse, as has the ERA, and at least recently, the WHIP as well. The only improvement seems to be the K/9 rate, some of which -- although certainly not all -- can probably be attributed to the advent of the designated hitter in 1973, which, combined with the complete decline of emphasis on the hitting skills of pitchers as time has gone by to the point where many pitchers, when not asked to bunt, simply stand up at the plate and flail away comically three times before slinking back to the dugout.

However, a funny thing happens if you look more closely at the year-by-year change in these numbers in the 2000s. Those stats tell a slightly different story:

"Day 4" starters in the 2000s

Apart from a big drop in wins in 2004, there's not a lot of difference in the first four seasons in this chart. Maybe I'm reading into these numbers too much, but look at the huge improvement in nearly every category -- ERA, K/9 rate, WHIP -- that took place in 2005. Was there anything that happened between those two seasons that might have influenced these numbers?

Yes, in fact, there was. On March 17, 2005, a few weeks before the season started, the hearing in front of Congress with Mark McGwire, Sammy Sosa, Jose Canseco, Rafael Palmeiro and Curt Schilling took place. It's only a theory, but perhaps the increased scrutiny on the topic of performance-enhancing drugs -- especially as it related to hitters -- was enough of a deterrent to actually tip the scales greatly in favor of the pitchers, as widespread use of PEDs decreased.

The following spring, Major League Baseball instituted its current drug testing program, which among other things, included a 50-game suspension for the first positive test for steroids. Again, I think it's more than coincidence that suddenly these pitching numbers went way into the tank in 2006. It has to be believed that some pitchers were indeed using PEDs before drug testing fully kicked in, and it only makes sense that many staffs around the league would not necessarily turn out the same had this form of cheating not ceased. As such, the backs of many rotations were probably far weaker in 2006 than they had been in quite some time.

Ever since "the purge" took place, though, you can see a steady improvement in these stats to the point where they appear to be far closer to 1980 levels than ever before. Again we realize this is an inexact analysis, but even at an anecdotal level, the conclusion seems consistent with common sense. It is clear to me we are entering a golden age of starting pitching. Those six unimpressive names from this year's roster of Day 4 starters actually posted a combined 3.09 ERA on Thursday and they were far from the best of the bunch. Once pitchers like Brandon Webb, Cliff Lee, Erik Bedard, Scott Kazmir, Jeff Francis, Joe Blanton, Gil Meche and Dustin McGowan start being activated from the disabled list, the depth of pitching in the major leagues will increase even more.

In fact, a brief snapshot of the combined numbers of the 120 most frequently used pitchers (30 rotations, four slots deep) continues to bear out our initial observations. Certainly, we're not ever going back to the days when complete games were the norm, but in terms of power and control, pitchers are certainly building momentum toward a return to the days when pitching, rather than home run power, was the skill that ruled the day.

Key pitching indicators

We may never see another statistical quartet of hurlers as we did with the 1971 Orioles, but with the trios we do have in San Francisco and St. Louis, promising young rotations like those in Toronto and Oakland, and standouts like the "4-H Club" (Roy Halladay, Dan Haren, Felix Hernandez and Cole Hamels) shutting opposition hitters down on a regular basis, the mound is where you need to start looking for the difference makers in baseball, in both real life as well as fantasy.

AJ Mass is a fantasy baseball, football and college basketball analyst for ESPN.com. You can follow AJ on Twitter or e-mail him here.