Mike grew up in Cuba before Fidel Castro came to power. He was a ballplayer. My recollection of him is how much fun he had playing ball. The story is that he was discovered while pitching for a Cuban army team. The Reds picked him up and had him playing in local Havana. He came up for a couple of games and was hit hard. He went back to the minors and roamed around several years. He had a little bit of a chance with the Cards in 1964, but they traded him to the Astros in 1965.
He made a team's rotation for the first time in 1966 at the age of 29. However after he took a step back in 1968 (at age 31) the Astros cut their losses and sent him to Baltimore for Curt Blefary. Orioles really got the better of that deal. Mike really kicked it up a notch and became one of the elite pitchers in the American League. He won a Cy Young in 1969 with 23 wins (and wasn't an All-Star). From 1969 through 1974, he won at least 18 games/year.
Mike was so-so in the postseason. He had a lot of opportunities, because the O's were always there. In 12 postseason starts, he was only 4-4, but his ERA was only 2.85. Those numbers would deify anyone now.
1975 was the start of Mike's decline. He really fell in 1976 and only got into a few games in 1977. Too bad that he didn't start having success until later on. He'd have had quite a career if he wasn't such a late bloomer. That, however, may be more a matter that he was a screwball pitcher and he it took a while for him to perfect it. At age 42, he tried to come back, but could only make it in the Mexican League, but he had a winning record at 7-6. Remember, in the late 70's we really didn't see anybody pitching in their 40's (except knuckleballers like Hoyt Wilhelm).
Mike has been a pitching coach in the Independent leagues lately. He's been in Orioles spring training this year, but as a special instructor and not as a prospect. He's only 71.