Complex sentence: When the year ended, however, Tanner was still the manager so, Tenace became a coach at the Major League level with the Houston Astros in 1986 and 1987, and later coached with the Toronto Blue Jays from 1990 to 1997.
Split into simpler sentences: When the year ended, however, Tanner was still the manager. So Tenace became a coach at the Major League level with the Houston Astros in 1986 and 1987, and coached with the Toronto Blue Jays from 1990 to 1997.