The United States earned a disappointing 1-1 draw in its opening match of Group B play at the 2017 Gold Cup.
Bruce Arena's squad is short on U.S. national team regulars and that reality was reflected in an experimental XI with the likes of Dom Dwyer, Dax McCarty and Kelyn Rowe all starting the match in Nashville.
Rowe tested the Panama goalkeeper from distance in the fifth minute, but his well-hit shot was punched from harm's way by Jose Calderon.
Chances were hard to come by, but Panama was finding space down the right flank, twice sending in crosses that tested the U.S. defense in the opening 25 minutes.
Jorge Villafana set Rowe up for another chance in the 26th minute with some nice interplay, but the New England Revolution winger's volley was again punched away by Calderon.
Panama countered straight after and Miguel Camargo's right-footed shot, after cutting in from the left, forced Brad Guzan into a fingertip save in the U.S. goal.
Kellyn Acosta found himself in a great scoring position right before half-time with the ball bouncing to him at the top of the penalty area, but his spinning first-time volley skipped to the left of Calderon's goal.
Ismael Diaz had one last chance for Panama before the break, cutting across the top of the 18-yard box and firing a low, line drive just wide of Guzan's goal as the teams went to the dressing room tied 0-0.
Dwyer got the U.S. off to the perfect start in the second half after a disjointed opening 45 for the Americans. The Sporting KC striker redirected a Rowe cross into the area with a first-time shot that snuck just inside Calderon's far post to give the U.S. a 1-0 lead.
Panama was almost level minutes later after a Gabriel Torres close-range header was saved by Guzan to the feet of Diaz, who fired over from just in front of the goal.
Hernan Gomez's team, firmly on the front foot, found an equaliser after an excellent Guzan save dropped right to Camargo, who clipped home a shot from eight yards away.
Jordan Morris came on late in the second half as Arena tried to spark the U.S. attack, but despite some quality moments, the Seattle Sounders striker couldn't push his team to the win.
The United States' second match is against Martinique on July 12, with Panama facing Nicaragua on the same day.