Here, as far as I can tell, is what we know to this point in time as far as the historical significance of Josh Hamilton's 5-for-5, four-homer night:
● To clarify an earlier tweet, Hamilton now boasts only the 16th four-homer game dating back to the inception of Major League Baseball in 1871. His feat now ranks as only the 14th four-homer game in modern major league history (1901-present), as two of those four-homer efforts came about in the mid-1890s. To frame the rarity of this accomplishment in the appropriate context, there have been only 21 perfect games thrown during the totality of major league history (again, dating back to 1871), with 19 of those being logged during the course of modern major league history.
● Hamilton's 18 total bases tonight are good for the outright all-time American League record, exceeded only by Shawn Green's 19 total bases during his 6-for-6, four-homer effort against the Brewers on May 23rd, 2002. Hamilton's fifth hit, a double, flirted with over-the-fence status, effectively leaving him just a couple feet shy of what would have been the only five-homer, 20-total base game in major league history. I imagine he'll be able to live with that shortcoming, though, so we should probably find a way to live with it ourselves. And in case you haven't figured it out by now, Hamilton pretty much obliterated every single-game Rangers offensive record, so there's that.
● Hamilton entered tonight's rain-threatened tilt in Baltimore sporting a .376/.435/.703 triple-slash line with 10 home runs in 128 plate appearances. He leaves the field tonight with a .406/.458/.840 batting line, and 14 home runs in 133 plate appearances. His wRC+ (a scaled offensive measure similar to OPS+, where a 100 wRC+ would be equal to league-average offensive production, and, say, a 150 wRC+ would be 50 percent better than league average) for tonight's game only was 1212. If you extrapolated his current regular-season numbers forward with not a lick of regression, you would find that he's currently on pace to hit his 63rd home run on plate appearance No. 599.
You would also find that his present 247 wRC+ is better than the very best full-season marks of Babe Ruth (235), Barry Bonds (245), Mickey Mantle (221), or Ted Williams (223), so, yeah -- Hamilton has performed at a level above that of a Hall of Famer at his peak over the first five weeks of the season. I couldn't tell you how many other 247 wRC+ runs of this length have ever been compiled in major league history, but I cannot fathom the list being too lengthy.
● There's also this:
Josh Hamilton has quadrupled Albert Pujols' homer count for the season in two and a half hours #realtalk— Joey Matches (@BBTiA) May 9, 2012
Josh Hamilton could go 0 for his next 210 and still have a higher slugging percentage than Albert Pujols.— Jeff Passan (@JeffPassan) May 9, 2012
It's funny what all you can get out of what may very well have been the single greatest offensive performance in the history of the American League.