You don't need a metric invented by guru Bill James to know that Ervin Santana's two-hit shutout Wednesday was a gem — and one of the best-pitched games by a Twin in recent memory.

But a James invention called Game Score does give us one way of measuring just how good Santana was — and just how rare his performance was in the context of recent Twins pitchers.

Game Score, per Baseball Reference, is derived thusly:

Start with 50 points. Add 1 point for each out recorded, (or 3 points per inning). Add 2 points for each inning completed after the 4th. Add 1 point for each strikeout. Subtract 2 points for each hit allowed. Subtract 4 points for each earned run allowed. Subtract 2 points for each unearned run allowed. Subtract 1 point for each walk.

As I understand it, in general, a game score above 60 is good. Above 70 is quite good. Above 80 is outstanding. Above 90 is one of the best-pitched games of a season. And above 100 is one of the best-pitched games of all-time.

And on Wednesday, Santana notched a Game Score of 91 — just the seventh game in all of MLB this season at 90 or more.

When you add up Santana's day in the context of the Game Score, you see how he racked up points: he allowed just two hits and zero runs. He didn't walk anyone. He struck out eight batters. And he worked the full nine innings.

Those factors are always going to help a Game Score — with low hit totals, working deep in a ballgame and high strikeout totals being the hallmarks of high numbers.

Those are also things Twins pitchers have generally been lousy at in recent years, which brings us to the more stunning part of Santana's game: he became the first Twins pitcher since Scott Baker in 2007 to produce a Game Score of 90 or better.

I counted 160 times between Baker's gem and Santana's gem that an MLB pitcher cracked the magic 90, but none for the Twins.

This perhaps shouldn't be terribly surprising given the aforementioned Twins deficiencies. Also, Johan Santana's last year with the Twins was 2007; he had the two most recent 90+ scores before Baker.

But even though it's just one metric, it is a pretty damning piece of evidence when it comes to convicting the Twins of not having top-flight starting pitching in recent years. When you think of an ace, you think of a pitcher who works deep into games, shuts teams down and strikes hitters out.

The Twins just haven't had those types of pitchers — and the Game Score doesn't lie.