JACKSONVILLE, Fla. — The band was not on the field, but it kind of looked that way for a few seconds on Sunday.
Cornerback Ambry Thomas made one of the 49ers’ best plays of the game in the team’s 34-3 victory over the Jacksonville Jaguars and if his sideline had been a little more patient, it would have turned out even better.
Thomas stripped wide receiver Christian Kirk of the ball, picked it up and began running toward the end zone.
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That’s when the mass confusion began with several coaches and players from the 49ers’ sideline spilling onto the field.
“Was I one?” 49ers coach Kyle Shanahan quipped. “Yeah.”
On his way to what could have been a 92-yard return for a touchdown, Thomas had to navigate people who wanted him to score as well as Jaguars players who wanted to bring him down.
Shanahan was one of the individuals from the 49ers’ sideline who was on the playing field during Thomas’ fumble return.
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After Thomas crossed the goal line, the officials got together and determined the 49ers were guilty of unsportsmanlike conduct. The touchdown was nullified, and the 49ers were assessed a 15-yard penalty.
Shanahan said he has nobody to blame but himself.
“I would have been mad at whoever did it,” Shanahan said. “I was mad at myself. I thought the play was over. We couldn't see, and everyone jumped up.
“So when that happens you're getting out there to start to congratulate people coming back, and they're not coming back to congratulate us, they're running back at us.”
The bizarre play figures to have a long life with the 49ers as a case study and a reminder to be more vigilant before entering the field of play.
“We know the rules, definitely,” Shanahan said. “We know you can't go on the field. I personally thought the play was over. They ran right by us.
“It was very unfortunate because it was a good learning experience for our team. We do show that stuff.”
Ultimately, the penalty did not cost the 49ers any points.
The 49ers put together a seven-play, 81-yard drive that Deebo Samuel capped with a 23-yard touchdown run for a 27-3 lead late in the third quarter.
“We can live with it, but it’s a good learning example for us,” Shanahan said.