Last month, the Giants lost their ninth straight game with Tim Lincecum on the mound, and I wrote about his struggles. Right after that, he put together two straight quality starts, including getting his third win of the season against the Dodgers. His last two starts before the All-Star Break were a disaster, though. He didn’t get through the 4th inning in either, and his ERA has ballooned back above 6.

Here are his full season numbers: 18 Games Started, 3-10, 6.42 ERA, 1.58 WHIP

He’s leading the league in losses right now. That earned run average is ugly. His velocity on the fastball is down and has been for a while. The Giants and Lincecum have denied any injuries, and he has continued to make every start, but the results are staggering. Last month, Jim Bowden raised the possibility of checking for an injury even if Lincecum is not feeling pain.

So, how unusual is this rapid decline for Tim Lincecum? The answer depends on how we define the decline. I can’t find anyone with as large a decline as Lincecum from his earlier baseline, but we still have half a season to go. Plenty of really notable pitchers have had an off year at age 28 and/or 29 where they were below average, after being one of the game’s best up until that point.

For example, Jim Palmer had a stretch somewhat similar to Lincecum in 1974 at age 28. From the end of April to mid-June in 1974 the Orioles went 1-8 in games he started, and he was shut down for two months with an elbow injury.

I enjoyed looking back through the old pitchers, for nuggets like getting to read about Noodles Hahn, a young phenom who retired a century ago with a dead arm before age 27. However, with apologies to Dizzy Dean and Ed Reulbach and Ernie Shore, I limited the rest of my look to players since the end of World War II. To find drop-offs before age 30, I took the best pitchers from age 23 to 27, and found those with the biggest decline in league-adjusted ERA at age 28 or 29.

Twenty names appeared on the final list, though we don’t know about Jake Peavy yet, and he just rebounded for an All-Star appearance after several years of injury struggles. In addition to Palmer, there are several notable names. Steve Carlton and Luis Tiant both led the league in losses at age 28 and had off-years where they were average pitchers at best. Don Drysdale had a losing record and below average ERA at age 29. Some notable pitchers changed teams and flopped: Mike Hampton to Colorado at age 28, and Barry Zito to San Francisco at age 29. Others fell off with serious injuries: Dean Chance, Mark Mulder, Bret Saberhagen.

The largest ERA decline was Robin Roberts, though Lincecum would need to recover to a low t0 mid 4 ERA to match that. Roberts gives some hope because the young Phillies phenom went through a down period in his late twenties (led league in losses twice, at 29 and 30), but did recover to pitch well in his thirties, last starting 20 games at age 38.

Will Lincecum recover? The hope has to be that he has a bit of a “dead arm” but no long term structural damage, and can rebound. Among the others who had a drop off, both the size of the decline from the previous baseline from ages 23 to 27, and the games played in the decline season were related to the chance of recovery. Of the five that started fewer than twenty games in the year they declined (indicative of injury), three never started twenty games again–Dean Chance, Mario Soto, and Mark Mulder.

You can find what you want in this list. You want hope, there are pitchers who rebounded. You want cause for concern, there’s plenty of that, too. Here is a summary of the remaining careers of the other pitchers with a drop off at age 28 or 29.

5 NEVER RECOVERED (No Other Seasons Of 20+ Starts, above average ERA)

Hal Newhouser (29), Dean Chance (29), Sam McDowell (29), Mario Soto (29), Mark Mulder (28)

6 PRETTY MUCH DONE, SMALL REBOUND (2 or Fewer Seasons of 20+ Starts, above average ERA)

Jim Maloney (28), Don Drysdale (29), Mike Hampton (28), Barry Zito (29), Bill “Spaceman” Lee (28), Mark Gubicza (28)

3 RECOVERED TO BE PRETTY GOOD IN THIRTIES (3 to 5 Seasons of 20+ Starts, above average ERA)

Robin Roberts (29), Dave Stieb (28), Bret Saberhagen (28)

5 WERE VERY GOOD IN THEIR THIRTIES (6 or more Seasons of 20+ Starts, above average ERA)

Steve Carlton (28), Bert Blyleven (29), Jim Palmer (28), Luis Tiant (28), Jimmy Key (28)

[photo via US Presswire]