For the second straight day, Leftwich took the majority of the snaps with the first team during Thursday's practice, while Brunell took none.
The left-handed Brunell is listed as questionable for Sunday with a cut on his left elbow. He said the elbow is fine, however, and he looked good throwing in individual drills early in practice.
Coach Jack Del Rio made the announcement shortly after practice.
"The injury plays into it a little bit," Del Rio said. "And I feel like this is our best option to help us win."
Leftwich will make his second career start. Last week, he threw for 231 yards with one touchdown, three interceptions and a crucial lost fumble in a 24-20 loss to Houston, which left the Jaguars 0-4.
"Whether I start or not is out of my control," Leftwich said. "I'm just going to prepare myself to play, the same as I always do."
Clearly upset with the decision, Brunell, a starter in Jacksonville since the 1995 expansion season, gave no theories for why it was made.
"You'll have to ask Jack," Brunell said.
Copyright 2003 by The Associated Press
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