Freeland lasted just three batters before leaving with a strained left groin
He made it 8 1/3 innings in a 10-0 Rockies' win over the White Sox before finally surrendering a hit to Melky Cabrera.
Freeland (7-3) allowed one run and six hits, struck out five and walked none while lowering his ERA to 3.34. The Denver native has turned in a quality start in eight of his last nine starts.
Freeland, 23, and Senzatela, 22, have each made six starts after their latest outings Wednesday and Thursday. Both have managed to post sub-3.00 ERAs.
Freeland gave up four hits with a pair of walks and struck out six, including the first batter up.
Freeland, who grew up in Denver and went to Thomas Jefferson High School, will make his major-league debut in the Rockies' 2:10 p.m. game against the Los Angeles Dodgers.
Kyle Freeland, who will start the Colorado Rockies’ home opener, was a big underwater seahorse racing guy in high school
The Rockies chose Freeland with the eighth overall pick in the 2014 draft
There's one less contender for the two open spots the Colorado Rockies have in their starting pitching rotation. The team announced Thursday that it optioned left-hander Jeff Hoffman to Triple-A Albuquerque.