Shakespeare said "Uneasy lies the head that wears a crown." It is not thought that Shakespeare was discussing baseball, but this we know: There has not been a triple crown winner in 36 years, and there hasn't been one in the National League since 1937.

All this may change thanks to the impressive play of Albert Pujols in his third year with the St. Louis Cardinals. As we near the midway point of the season, Pujols has already put together about as strong a first 2 ½ years in the big leagues as has ever been seen.

It's certainly premature to start triple crown talk yet – remember when we laid that on young Gary Sheffield in 1992? – but it's hard not to begin projecting Pujols for those kind of numbers.

As the season heads into the dog days of summer (which seem to start in San Diego around mid-April), Pujols and the Cardinals will make their only appearance of the season at the Q the week after the All-Star break, July 21-23.

By then we'll see if Pujols is keeping up his phenomenal pace. After getting four hits Thursday, Pujols goes into the final weekend of June leading the NL in hitting (.394 and rising), runs batted in (68), hits (112), doubles (30) and is three off the home run lead with 21. He also leads the majors in extra-base hits, slugging and total bases, is second to Barry Bonds in on-base percentage and has a combined on-base-plus-slugging percentage that's even higher than Bonds'.

To win the triple crown, a player must lead his league in batting, homers and RBIs.

The last NL player to do so was another Cardinal, Joe Medwick in 1937. Stan Musial, surprisingly, never led the league in homers. Sheffield, who had his breakout season with the Padres in '92, challenged in all three categories but ended up winning only the batting title (.330).

The last players to win the triple crown did it back to back: Frank Robinson, in his first season in the AL, won the triple crown with the Orioles in 1966, and Boston's Carl Yastrzemski did the trick the next season. Not coincidentally, their teams went to the World Series and each earned an MVP award.

The triple crown is rare enough that Babe Ruth never won one, but Lou Gehrig did. Joe DiMaggio didn't, but Ted Williams won two. Mickey Mantle did but Willie Mays didn't.

Often, it's been a matter of timing. When the Cubs' Hack Wilson set NL records with 56 homers and 190 RBIs in 1930, he also batted .356. But he didn't even place in the top five in batting. Three years later, Chuck Klein, another great NL slugger of that era, won the triple crown with 28 home runs – exactly half Wilson's 1930 total.

Mike Schmidt won two-thirds of the crown – homers and RBIs – four times but never challenged for a batting title. Hank Aaron led in homers/RBIs three times and won two batting titles but never managed to do all three in the same season.

Tony Gwynn helped keep Larry Walker from a possible triple crown in 1997 by outhitting the Rockies star .372 to .366.

Can Pujols overcome the odds? He certainly deserves watching.