ALLEN PARK, Mich. -

ALLEN PARK, Mich. -- When Jim Caldwell was hired as the head coach three years ago, he promised the Detroit Lions would be a more disciplined team.

The Lions routinely ranked as one of the most penalized teams in the NFL under former coach Jim Schwartz, and for parts of Caldwell's first two seasons the team improved in that respect.

But two games into this season, the Lions are back to shooting themselves in the foot with wild bouts of undisciplined play. In Sunday's 16-15 loss to the Tennessee Titans, the Lions committed 17 penalties for 138 yards and had three touchdowns nullified by flags.

Caldwell called his team's penalty problems "ridiculous," though he insisted they weren't due to a lack of composure.

"All I know is there were way too many," Caldwell said. "Whether or not it's a composure issue, composure issue is when you get personal fouls and guys are out of control and there are fights and things of that nature. These were technical issues, I think, that we had a bunch of issues with. A lot of different guys."

Eleven different Lions were flagged Sunday, and Eric Ebron, Anquan Boldin, Laken Tomlinson, Darius Slay and Brandon Copeland all drew two penalties apiece. (The Lions' last penalty was an intentional delay of game penalty on a punt.)

Ebron had a holding penalty that wiped out a touchdown run by Ameer Abdullah and was called for offensive pass interference in the end zone to negate his own touchdown catch. Tomlinson had a holding penalty that took a touchdown off the board.

The Lions took issue with Ebron's questionable pass interference flag, as well as a non-call on Titans defensive tackle Jerrell Casey for hitting quarterback Matthew Stafford below the knees, and Caldwell said he planned to send video to the league of several plays.

Still, Caldwell and several players said it's imperative that the Lions, who lead the NFL with 26 penalties (25 of them accepted) through two weeks, clean up their play heading into a crucial two-game road stretch against NFC North opponents the Green Bay Packers and Chicago Bears.

"We're trying to build a team that's steady and playing well the majority of the time," Stafford said. "We didn't do it (Sunday). We hurt ourselves. All that stuff is correctable. The penalties and missed assignments, drops, whatever it was, it's correctable stuff. We can get it taken care of and we will."

REPORT CARD VS. COLTS

PASSING OFFENSE: C-plus - Matthew Stafford completed just 22 of 40 passes for 260 yards, but he had a fine day before throwing an interception on his final pass. The Lions' usually sure-handed receiving corps had seven drops and a couple untimely penalties that took points off the scoreboard, and the offensive line had issues in pass protection in the second half. Marvin Jones led the Lions with eight catches for 118 yards.

RUSHING OFFENSE: B - The Lions ran for 137 yards, including 31 on two scrambles by Stafford, but didn't get a big day out of any of their running backs. Ameer Abdullah left in the first half with a foot injury and Theo Riddick averaged just 3.4 yards per carry. Rookie Dwayne Washington showed some flash in limited action, but the team didn't convert some crucial short-yardage plays.

PASS DEFENSE: B - The Lions allowed just three points in the first three quarters Sunday, but had no answer for Marcus Mariota in the fourth. Mariota completed all nine of his passes on the game-winning touchdown drive. Glover Quin intercepted a pass and Tavon Wilson was strong in run support, but cornerbacks Darius Slay and Nevin Lawson both had costly penalties and/or coverage breakdowns.

RUSH DEFENSE: C - DeMarco Murray ran for 89 yards on 12 carries as the Titans took advantage of the Lions' depleted linebacking corps. The Lions did a good job containing Mariota, but Tennessee averaged 5.8 yards per carry as a team. Devin Taylor beat rookie right tackle Jack Conklin for a safety in the first quarter.

SPECIAL TEAMS: A-minus - The Lions haven't got much out of their return game this year, but they haven't allowed any field-turning plays, either. Sam Martin had another solid day punting, dropping all five of his punts inside the 20-yard line. Matt Prater made 42- and 27-yard field goals, but the Lions passed on a potential 57-yarder in the second quarter.

COACHING: C - The penalty problems reflect poorly on Jim Caldwell and his staff, but that wasn't their biggest failing Sunday. The Lions gave up two touchdowns in the fourth quarter and have now allowed 30 fourth-quarter points through two games. Injuries played a role in that, but defensive coordinator Teryl Austin needs to find a way to stop the bleeding. Caldwell punted on 4th-and-3 from the 39 in the second quarter, when he could have trusted Stafford to make a play. And the Lions didn't challenge a Marcus Mariota scramble on 3rd-and-6 that was ruled a first down but appeared to be short on replay.