McCarthy scratched Rodgers along with nine other Packers, and Rettig wound up playing all but two snaps in the fourth quarter as Green Bay lost to the Tennessee Titans 20-16 on Saturday night.
"Aaron's situation of not playing was more about us having four quarterbacks," McCarthy said. "Historically, I feel like I didn't do a good job of getting the fourth quarterback reps, so we made a point to make sure our young players had the whole fourth quarter.
"I feel like Aaron's had an excellent camp and a phenomenal spring. He would have played one series tonight, so it was really about getting Chase the work in the whole quarter."
Mason Crosby kicked a 32-yard field goal with 7:07 left, putting the Packers up 16-13. But Rettig, the rookie out of Boston College, was sacked twice and he also threw incomplete on fourth-and-1, missing Kevin Dorsey at the goal line inside the final minute.
Jackie Battle scored on a 7-yard touchdown run with 5:02 left. Tennessee rookie Zach Mettenberger made up for two turnovers in the fourth quarter by completing all three passes for 71 yards to set up Battle's go-ahead touchdown for Tennessee's first lead.
The game was played mostly in a pouring rain. Titans coach Ken Whisenhunt, a winner in his debut, said it was the worst weather he's coached in, though he once played in uglier conditions.
"A lot of things we had planned went out the window with the rain, so for nothing else it was a good opportunity to work on that," Whisenhunt said. "We learned a lot about ourselves and what we have to do to prepare for that. Those aren't conditions you generally replicate or practice."
Quarterbacks had trouble holding onto the ball with the Packers fumbling five times, losing only one. Tennessee lost one of three fumbles.
"We probably didn't do quite as good as we'd like there with the number of times we had the ball on the ground and with the drops," McCarthy said. "To play in this environment was an incredible experience for our team."
Not so much for the fans. The biggest cheer of the game came early in the second quarter, when rain finally eased up for the first time in nearly two hours. But heavy rain returned late in the first half and stuck around most of the third quarter.
Davante Adams fumbled a punt in the first quarter that led to the Titans' first touchdown, a 13-yard run by Shonn Greene, who's had two arthroscopic surgeries in the past year on his right knee. Rookie Bishop Sankey caught a 5-yard TD pass from Charlie Whitehurst.
Flynn started and was 5 of 10 for 49 yards playing most of the first half. He left with the Packers leading 7-6 thanks to James Starks' TD capping the opening drive. Starks played only the first series in place of Lacy, and he finished with six carries for 49 yards.
"Physically it's just one of those weird games," Flynn said. "You can't really go back and critique your mechanics, and receivers can't really critique their routes too much because it was a sloppy game."
Tolzien simply lost the ball out of his hand trying to pass midway through the third quarter, then he grabbed the jersey of Titans linebacker Brandon Copeland holding until he could recover his fumble. Tolzien then found Chris Harper for a 38-yard pass, and rookie Rajion Neal, who played at the University of Tennessee, capped the drive with a 12-yard TD run early in the fourth quarter.
The sloppiness wasn't limited to players on the field.
After Neal's touchdown run was reviewed, the Packers sent the offense out a 2-point conversion pass that failed. The TD was taken off the scoreboard with some thinking the TD had been overturned.
Notes: LB Joe Thomas injured his knee and did not return for Green Bay.
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