"We're making too many mistakes," Mularkey said. "We have to overcome ourselves first. Before we can beat anybody, we have to stop beating ourselves."
Also against Indy, the Jaguars were flagged for six personal foul penalties, Josh Scobee missed a 44-yard field goal, Gabbert's interception was returned for a touchdown and several video replays went against them.
The 15-yard penalties were still bothering Mularkey on Friday, especially the one called on the coach.
Mularkey expressed his displeasure with a seemingly quick scoring review in the second quarter by throwing his play sheet and headset onto the field. Mularkey thought officials should have taken a longer look at Andrew Luck's 1-yard TD run on fourth down, a play in which Luck appeared to lose control of the ball as he neared the goal line.
Mularkey was flagged for his response — his first penalty as a coach.
"I am really not very proud of it to be honest with you," he said. "It's not good for your football team to show that kind of frustration to them. It kind of sends a sign that it's OK, and it's not OK.
"I think it has a direct influence on the officiating crew that you're questioning them and putting them on the spot, and that may result in things later on being called that maybe were grey because of what I did. That was not a good decision on my part."
The Jaguars fell to 0-5 at home, having been outscored 153-44 in lopsided games against Houston, Cincinnati, Chicago, Detroit and Indianapolis.
"I don't think any of us thought that we would be in this position," Mularkey said. "I know our team didn't feel like we'd be in this position. ... We're not looking back. We're moving forward. We're going to try to continue to gain progress in what we're doing. It's disappointing because none of us felt like we would be here by any means."
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