Matt Cain, ace of the Giants’ world championship teams in 2010 and 2012, saw his performance fall off sharply in 2013 and was a non-factor in 2014, pitching ineffectively through the first half of a season that was cut short by a wonky elbow. After surgery, Cain is said to be feeling fine and raring to go for 2015.

But, is there a reasonable expectation that Cain can regain the elite form he displayed prior to 2013? I’ll look at that question after the jump.

Cain is in a group of 40 pitchers since 1901 with 1500 IP and a 115 ERA+ through their age 27 seasons. Cain’s 124 ERA+ over that period is right at the median point of the group that includes no fewer than 17 HOFers plus the Hall-worthy Roger Clemens. Joining Cain as active players in the group are Felix Hernandez and CC Sabathia.

With such a solid group, one might expect continued stellar performance as these pitchers entered their age 28 and age 29 seasons, presumably still in their primes. In fact, there was a notable drop off in performance across the group, with median ERA+ declining from 124 to 109 and only 12 of the 40 pitchers maintaining or improving on their ERA+ over those two seasons (one of the twelve being Felix Hernandez, based on just his age 28 season).

Matt Cain’s 85 ERA+ for age 28-29 is easily the lowest of the group and the only pitcher to drop below 90 for those seasons. To assess Cain’s prospects for regaining his form, I looked at pitchers from the group with the highest drop in ERA+ at age 28-29.

1. Walter Johnson A surprise, perhaps, but Big Train’s 133 ERA+ age 28-29 was 43 points below his group-leading 176 result previously. As you already know, Johnson did just fine afterwards, especially immediately after, leading the majors in ERA+ at age 30 and 31, both times with a score exceeding 200.
2. Matt Cain’s 39 point drop is the second largest of the group of 40.
3. Dave Stieb saw his ERA+ plummet 36 points, from 135 to 99, but rebounded to a 125 ERA+ over his next 3 seasons, each with over 200 IP.
4. Robin Roberts dropped 33 points, from 132 to 99, and kept on falling to 93 ERA+ and a 10-22 record in his age 30 season. He rebounded to 123 at age 31 but dropped below 100 in the two following seasons before cratering to a 1-10 record and 69 ERA+ at age 34. Seemingly done, Roberts caught on with the Orioles and rose phoenix-like to a 119 ERA+ in over 800 IP aged 35-38.
5. Doc White skidded from 128 to 97, but rebounded to a 137 mark at age 30. But, that would be White’s last season with a stellar ERA as he finished his career with 97 ERA+ in 700+ IP aged 31-34.
6. Bert Blyleven dropped 30 points, from 132 to 102, but improved to 127 with a return to the AL for his age 30 season. Injury sidelined the Dutchman for most of the next season and parts of the following campaign, but Blyleven rebounded again with a 138 ERA+ in over 500 IP aged 34-35.
7. Vida Blue dropped 28 points, from 118 to 90, the latter mark the second lowest of the group. But Blue rebounded nicely, with a 126 mark aged 30-31.
8. Dennis Eckersley had the same 118 ERA+ as Blue through age 27 and fell almost as far, to a 92 mark aged 28-29.  Eck responded with a 129 ERA+ in his age 30 season, but was lit up with a 4.73 ERA in his last six starts after returning from the DL. His form did not return the next season as he dropped to an 88 ERA+ in 201 IP. That would mark the end of the first half of Eckersley’s career as a trade to the As ushered in his transformation to baseball’s premier closer.
9. Dutch Leonard dropped from 126 to a 101 mark in 1920-21, seasons in which Leonard reportedly was forced to rely more on his spitball. After the Tigers wouldn’t meet Leonard’s contract demands following his age 29 season, the mercurial southpaw jumped to an independent team in Fresno, earning a two-year ban from organized baseball. Returning to the Tigers at age 32, Leonard had run-ins with his equally hot-tempered manager Ty Cobb and never came close to regaining his earlier form.

Leaving aside Leonard, all except Roberts posted a solid age 30 season and all but White and Eckersley turned in a good age 31 campaign. So, on that basis, there would seem to be reason for optimism for a return to form for Cain.

The nagging question, though, is will Cain recover from his injury and surgery. To see how others had done following injury and sub-par performance at age 29, I looked for pitchers in the group with less than 150 IP and an ERA+ below 100 in their age 29 season. That turned up Cain and these four pitchers.

1. Dwight Gooden‘s troubles were self-inflicted as his age 29 season in 1994 was cut short, first by a suspension for drug use and later by the players’ strike that year. Another failed drug test would earn Gooden a suspension for the entire 1995 season.
2. Nap Rucker developed a “sore arm” in his age 29 season and never regained his form.
3. Lefty Leifield had developed a “sore arm” at age 28 and lasted only 21 innings in his age 29 season. Leifield never regained his earlier form, though he did tough it out in the minors for four years before making it back to the majors with some success (104 ERA+) in very limited innings at age 34-36.
4. Eddie Rommel apparently did not suffer an injury. Rather, with the powerhouse As pitching staffs of the late ’20s and early ’30s, Connie Mack relegated Rommel to the role of utility man, but still a valuable pitcher. His 97 ERA+ at age 29 was just a one-year blip as he rebounded to a 131 mark aged 30-33 in over 100 IP each year, but only once above the modern qualifying standard.

So, probably not much help in assessing Cain’s prospects as our two injured pitchers were both long ago and likely received no therapy other than rest.

So, what is your prognosis for Cain?