The Colts held a 13-0 lead at halftime against a winless Tennessee Titans squad, one which could only muster 64 yards of total offense over the first 30 minutes.

So how, exactly, did the Colts head back into their locker room at Lucas Oil Stadium a few hours later having lost, 26-20, to those same Titans?

Just about everything that could go wrong in the second half went wrong, for starters.

"Extremely disappointing," head coach Shane Steichen said. "We got a lot to fix, and we gotta fix it in a hurry."

Running back Jonathan Taylor lost a fumble on the Colts' first play of the second half, and on the ensuing possession, cornerback Sauce Gardner left the game with a calf injury and did not return. The Titans got their first points of the game there, with kicker Joey Slye connecting on a 29-yard field goal.

The Colts' offense then went three-and-out, but got a break on a running into the kicker penalty (which, as it turned out, may have been a harbinger of things to come). But the Colts' offense couldn't take advantage of their good fortune, with quarterback Daniel Jones throwing an interception on a first-and-10 from the Titans' 24-yard line when cornerback Cordale Flott sank in front of a Will Mallory corner route.

"I think he knows he's gotta play better, I gotta coach better," Steichen said. "There's a lot of things. It's not all one guy. But we've got to do a lot of things better."

"I don't think it's been consistent enough," Jones said of his play. "I think certainly today wasn't consistent enough."

Tennessee then plowed 51 yards on nine plays to set up a long Slye field goal, drawing them within a touchdown late in the third quarter.

After an offensive possession stalled with Jones being sacked, Titans return man Chimere Dike ripped off a 58-yard punt return to the Colts' 28-yard line. Quarterback Cam Ward finished it off with a game-tying touchdown to wide receiver Carnell Tate.

Again, the Colts' offense stalled – this time, they were unable to recover from being backed up to second-and-20 due to a holding penalty assessed to center Tanor Bortolini. Disaster then struck when Titans running back Julius Chestnut blocked Rigoberto Sanchez's punt, with defensive end Oluwafemi Oladejo running it back for a go-ahead touchdown.

The Colts responded with a game-tying touchdown drive, marching 72 yards on eight plays without facing a third down to tie the game.

But with five and a half minutes left, the Titans immediately took a shot at Gardner's replacement, veteran Cam Taylor-Britt, who was flagged for a 36-yard pass interference penalty that moved the ball near midfield. Slye connected for a go-ahead field goal just before the two-minute warning.

The Colts' offense, though, couldn't overcome Jones being sacked on a third-and-10; later, Jones threw a pair of Hail Mary passes that fell incomplete.

And that's how the Colts squandered a game they felt was very much winnable against a team that hadn't won a game before Sunday.

"Every single person on the team needs to be hard critics of themselves and figure out what they can do better and learn from this tape," defensive tackle DeForest Buckner said. "Just take ownership of what we put on tape and move forward."

Safety Cam Bynum said a loss like this one makes "us sick to our stomach," but emphasized the Colts need to regroup quickly without letting this one sting for too long. Running back Jonathan Taylor echoed the sentiment of this team figuring out how to fix these issues quickly.

"It's on us. No one's coming to save us," Taylor said. "You got to look yourself in the mirror and figure out what type of team that you want to be. And if you want to be a really good team, you can't lose divisional games at home."

After Sunday's game, Steichen, Jones and Buckner all admitted they heard the boos that came from the stands at Lucas Oil Stadium on Sunday. And each of them said they understood why fans expressed their displeasure.

"They're upset," Buckner said. "We lost to the Tennessee Titans, who were 0-5, now they're 1-5."

"We didn't play well enough today," Jones said. "We've got to play better and give them something to cheer about."

"We gotta give them something to cheer about," Steichen said. "I don't blame them for booing one freaking bit."