A year ago at this time, the Oakland Athletics were strong favorites to make the playoffs for a fifth consecutive year. The single biggest reason was their trio of young aces – Tim Hudson, Barry Zito, and Mark Mulder. Zito had a rough April, but settled down in the next two months, while Hudson and Mulder looked like Cy Young contenders right out of the gate.

In July, things went off the rails. Zito was tattooed for a 5.97 ERA, Mulder for a 5.11, and Hudson missed the entire month. Zito would go on to pitch respectably, though below his usual standards, for the rest of the year, and Hudson completed the season with a 3.53 ERA. But Mulder just kept getting worse and worse down the stretch as the A’s eventually finished a game behind the Angels in the A.L. West race.

This past winter, Hudson was traded to the Atlanta Braves and Mulder was sent to the St. Louis Cardinals, both in exchange for young players and prospects. All parties insisted that both were healthy, so the trades were probably made simply because A’s General Manager Billy Beane, who didn’t have the money or the inclination to sign his pitchers to long-term deals, felt it best to follow Branch Rickey’s old maxim: “Better to trade a player a year too early than a year too late.” It made sense to hold onto Zito, who turns 27 next month, since he had two cheap years remaining on his contract, faced no health questions, and would have fetched the least in the trade market because he had the worst 2004.

The real question here isn’t whether trading Mulder, 27, and Hudson, 29, was the right call; it almost certainly was. What Beane got in return seemed questionable, but we don’t know what was offered or whether he absolutely had to move two of his big three.

More interesting to me is the question of why Zito and Mulder, who are sporting, respectively, Eras of 11.57 and 8.18 in 2005, appear to have collapsed. Taking the word of all involved that there are no health issues at play, this doesn’t appear to reflect well on the A’s vaunted approach to pitcher development.

That approach is based on drafting polished college starters and using a coherent, system-wide approach in which pitch efficiency and mechanics are carefully monitored. It seemed for a while that the A’s had discovered how to keep young pitchers throwing huge numbers of innings at a high level of effectiveness without damaging their arms. Now it’s starting to look like they got lucky with a few good starters, and might have ridden them into the ground.

The problem is serious. Through the end of last June, Mulder had given up 3.94 runs per nine innings in his career; since then, he’s given up 6.87 per nine in 118 2 / 3 innings of work. Zito, before Opening Day of last year, had given up 3.50 runs per nine; since then, 5.30 in 222 1/3 innings.

In Zito’s case, the problem can be pinpointed in two numbers. Before the 2004 season, he gave up a hit to 19% of the batters he faced, and a home run to 2%; since, those numbers have gone up to 24% and 3%. The rest of his statistical profile is fairly stable. The hit rate is partially outside of Zito’s control – luck and defense play a big role there. Giving up half again as many home runs as he did, though, is a worrying sign.

Not so worrying, though, as the staggering drop in Mulder’s performance since last July 1. Like Zito, Mulder’s home run rate has gone up by 50%, and his hits-allowed rate by about 20%; unlike Zito, this has been accompanied by a dramatic drop in strikeout rate and a huge rise in walk rate. Through last June, Mulder had walked 7% of the batters he’d faced in his career; since, he’s walked 10%.

Judging by what I’ve seen from the two, and from these numbers, I’d say there’s a pretty good chance Mulder is done as an elite starter, and that Zito’s career may end up resembling Andy Pettite’s – a brief flash of brilliance followed by a long stretch as a decent starter who contributes more by being durable than by being brilliant.

Why is this? My suspicion is that Zito and Mulder are examples of the downside of Oakland’s approach (which is of course not limited to Oakland). Traditionally minded organizations stress physical ability over performance for a reason. Polished college starters without overwhelming stuff, like these two, have a real problem when they reach their late-20s and lose a few miles an hour off their fastballs, or a bit of movement on their breaking pitches – a process the A’s may have hastened by placing heavy workloads on them.

A pitcher who starts off throwing in the 90s, like Hudson, still has enough stuff once he loses a bit of his edge; someone like Zito, who rarely broke 88 mph even as a Cy Young winner, may not. Drafting such a player, you may get his big years up front.

It’s probably time to lower expectations for these erstwhile aces, and to appreciate how historically rare the Greg Maddux/Tom Glavine/John Smoltz troika – two of whom had even less stuff than Zito – really was. Hudson always was the best of the A’s big three, and now that he’s in the care of the Braves – who have an unparalleled record of keeping pitchers effective and healthy through such simple techniques as having them throw on their off-days and use their fastball for as many as 90% of their pitches – he’s a very good bet to remain so.