Who's the greatest DH of them all? (Getty Images)

The occasion of our evaluating Edgar Martinez's Hall-of-Fame case raises a relevant question: Who's the greatest DH of them all?

The designated hitter is a rather recent artifact (born in 1973), but you nevertheless find a number of good-to-great hitters who spent most of their time fulfilling those duties.

So there are two ways to approach such an urgent matter. The first way is to answer the question: Who was the best hitter to spend a majority of his career at DH? If that's the guiding query, then the discussion will be a brief one. It's Frank Thomas (career OPS+ of 156), and it's not a close call.

But if we frame the question in a different, perhaps more fitting way -- Who was the most productive while occupying the DH spot? -- then things get more interesting. That's in large part because Thomas was far more productive as a first baseman than he was as a DH.

If we stipulate that contenders for "best ever while manning DH spot" must have logged at least 5,000 career plate appearances and have spent at least half of those PAs at DH, then our list of contenders is down to six: Thomas, Martinez, David Ortiz, Hal McRae, Harold Baines and Don Baylor.

Let's compare some numbers, shall we? Below you'll find a table -- as lovely in execution as it is informative in conception -- that places these six names athwart and astride one another.

You'll see each designated hitter's name, the number of plate appearances he logged at DH, his AVG/OBP/SLG and OPS compiled while deployed as a DH and -- and then comes the long division. Actually, it's pretty simple. Under the heading "OPS/Avg. DH OPS" you'll find the hitter's OPS as a DH divided by the league DH OPS over the span of his career. Ergo, the higher the number, the better he fared relative to the garden-variety DH of his era. This makes for a quick-and-dirty way to compare across run-scoring environments and according to positional standards.

To the digits …

Who is the greatest DH?
Player PA as DH AVG/OBP/SLG OPS as DH OPS/Avg. DH OPS
Edgar Martinez 6,218 .314/.428/.532 .959 1.21
David Ortiz 6,523 .288/.384/.557 .941 1.16
Frank Thomas 5,698 .275/.394/.505 .899 1.12
Hal McRae 5,917 .294/.357/.463 .820 1.10
Harold Baines 6,618 .291/.370/.467 .837 1.07
Don Baylor 5,391 .259/.344/.449 .792 1.06
Sorted by OPS/Avg. DH OPS

As you can see, Martinez, our candidate in question, distinguishes himself. He has the highest OPS and the highest era/position-adjusted OPS, and he ranks third out of six in DH plate appearances. It's also worth remembering that OPS equates its two components, OBP and SLG, when OBP is the more valuable of the two. Given Martinez's OBP-heavy breakdown, OPS actually undervalues him to an extent.

Park effects? Contrary to reputation, Seattle's Kingdome played as a roughly neutral environment over Martinez's time as a regular there, and he spent the back end of his career in run-suppressing Safeco. As for Ortiz -- Martinez's closest competition based on the above numbers -- his home park of Fenway is a tough yard for left-handed home runs, but it's a very accommodating park for every other facet of the left-handed hitter's game (i.e., singles, doubles and triples). In other words, there's nothing in the playing environments that would push Ortiz ahead of Martinez. That's to say nothing of the fact that Baseball-Reference and FanGraphs each rate Martinez as the better base-runner of the two.

Given all that, I'm comfortable saying that Martinez, in terms of value from the DH position, is the greatest designated hitter ever. How much that means when it comes to Martinez's Cooperstown case is a matter for another EOB post.

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