It was only a matter of time before USC quarterback Matt Barkley lost his cool.
It finally happened Tuesday, with the junior snapping at a walk-on wide receiver who ran the wrong route.
The only surprise might be that it took this long, working with a banged up group of receivers and running backs, a true freshman fullback and an offensive line low in numbers and experience putting him under constant duress.
"It's just frustrating because things should be going a certain way," Barkley said. "I'm at the point where I know what's going on and know my reads and then someone else messes up and it throws me off.
"But it's important to just keep your cool and realize that these are young guys and you have to kind of coach them at the same time. I was probably the same way when I was younger."
Barkley's attitude was even less surprising coming off a disastrous offensive showing Saturday at the Coliseum. Only D.J. Morgan's short touchdown run at the end of the scrimmage prevented a shutout.
Reviewing the film did not change Kiffin's impressions of the team's execution and, more importantly, effort.
"Really disappointed in our ability to finish and play really hard," he said. "We've got to push through that. We've got to play extremely hard. Way too many loafs. It's just a reminder that we're in spring, not the fall, thankfully."
"In a way it was good to have that happen so our players can see how far away we are."
Kiffin said the biggest issue with Barkley is not letting his frustration lead to errors on the field, as happened Tuesday when he lobbed a pass that was easily intercepted by cornerback Nickell Robey.
"That's what you have to fight through. He's had an issue with that since he's been here," Kiffin said of Barkley.
Barkley agreed with that assessment, something he hopes to show to fans during the spring game Saturday at the Coliseum.
"Not looking to have a huge flashy numbers game and all that stuff," he said. "I don't think we've had one to this point, but looking to be really consistent in how I play and be smart with the ball."
The Trojans went through a service team period for the first time this spring, so the offense and defense could see looks they will face in Pac-12 play.
Kiffin also said the team would practice in full Thursday, though it would be in helmets and shorts per NCAA rules.
-Cornerback Tony Burnett and safety Demetrius Wright each missed practice with left ankle injuries suffered during the scrimmage Saturday.
"It's a little tender, so they got me in a boot until further notice," Burnett said. "They want to make sure I'm healthy for the (final) scrimmage."
Running back Dillon Baxter (ankle) and Marc Tyler (concussion) also missed practice and are questionable for the spring game this Saturday.
-Wide receiver Markeith Ambles was held out of practice after being late to a team meeting Tuesday morning. Ambles ran and did other conditioning drills as punishment.
-Former wide receiver and graduate assistant Keary Colbert worked out with the team, though he was not in helmet and pads per NCAA rules.
Colbert dropped a few passes and told Kiffin afterwards he felt like rolling in the grass as punishment.