ARLINGTON, Texas – The Cowboys had 15 days, a trade for new receiver Amari Cooper and firing of their offensive line coach to prepare for a 3-4 Tennessee Titans team. Still, they struggled to produce at home.

The result: Dallas surrendered its first loss at AT&T Stadium this season, dropping to 3-5 and generating more questions about head coach Jason Garrett’s status with the team.

The two teams screamed of symmetry at times, from turnovers by quarterbacks Marcus Mariota and Dak Prescott (two each) to both teams missing a field goal.

But the Titans came through when it mattered in the 28-14 win. The Cowboys repeatedly fell short.

Here are three things we learned about the Cowboys and Titans:

1. Turnovers galore: The Cowboys defense started quickly, with linebacker Sean Lee recovering a fumble after DeMarcus Lawrence notched a strip-sack on Mariota with 8:18 to play in the first quarter. Just one drive later, linebacker Jaylon Smith recovered Mariota’s second fumble.

Tennessee’s defense followed suit. Free safety Kevin Byard picked off Prescott, who was targeting new acquisition Amari Cooper, in the end zone in the first quarter and celebrated Terrell Owens-style on Dallas' midfield star. On third-and-13 in the third quarter, Prescott lost another ball. Titans linebacker Jayon Brown pulled off the strip-sack this time and Wesley Woodyard recovered at the Dallas 40.

Prescott now has turned the ball over twice in 10 games since the beginning of 2017, bumping him into a four-way tie for league-worst with Jameis Winston, Derek Carr and DeShone Kizer. Kizer and Winston have each lost their starting jobs in that stretch. Carr has lost Cooper.

Efficient Titans: Neither the Cowboys nor the Titans were consistent, but Tennessee capitalized when it mattered. The Titans converted on third down 79 percent of the time (11-of-14) to Dallas’ 45 percent (5-of-11). Tennessee also won in the red zone, scoring on four of five trips to Dallas’ one of four. Mariota looked the part of superior mobile quarterback, extending Tennessee’s lead to 28-14 with a 9-yard score in the game’s final five minutes. Mariota rushed eight times for 36 yards – including several third-down conversions – and a score on the day to complement his 21-of-29, 240-yard passing performance.

Prescott, who rushed 11 times for 82 yards in Dallas’ last home game (40-7 win over Jaguars), carried just twice for 11 yards in the loss.

Cooper provides a boost: Cooper led Cowboys receivers in his first game with 58 yards and a score, catching five of eight targets from Prescott. But the receiver Dallas forfeited a 2019 first-round pick for wasn’t a cure-all solution Monday night. Ezekiel Elliott averaged just 3.59 yards a carry (61 yards on 17 tries) while he amassed 112 total yards.

Prescott finished 21-of-31 for 243 yards, two touchdowns and two turnovers.

Follow Jori Epstein on Twitter @JoriEpstein.