The Jets, after last week's preseason-opening victory over Tennessee, got some good vibes but also were under no illusions. And after tonight's 16-6 loss to the Lions at Detroit, they know there is plenty of work before the season opens Sept. 10 in Buffalo.

The Green & White front-line offense (43 first-half yards) struggled to move the ball with Christian Hackenberg under center. And while the defensive starters had some highlights, the D also yielded two long first-half scoring drives.

Here are five takeaways from the Jets' loss to the Lions, their third in the last five years in the unfriendly confines of Ford Field:

1. Hack Gets the Nod
Bowles told WCBS' Otis Livingston right before kickoff that the plan was to play just two Jets QBs — Hackenberg to start, Bryce Petty to follow in the second half. Hackenberg's first three series were 3-and-outs, although the two sacks he suffered were on blocking problems. But the rest of the half wasn't much better as Hack finished with two completions in six passes for 14 yards and had five full series, all ending in punts and four in 3-and-outs.

Hackenberg did get to use RB Bilal Powell, whose first action of preseason netted 32 yards on nine carries and 14 yards on two catches.

"It's all part of the process. You can't look at numbers or stats. You've just got to go back to the tape and review it," said Hackenberg. "Overall, I thought it was a good learning experience."

2. Ball's in Petty's Court
Petty started out strong, completing 10 of his first 14 throws for 102 yards. His first drive got close enough for Ross Martin to try a 56-yard field goal, which drifted just left. His third drive penetrated into the red zone and Martin hit from 31 yards, cutting the visitors' deficit to 13-3 and ending the Jets' scoring drought of 22 straight drives (last 14 series vs. Titans, first eight vs. Lions). Then another short drive and another short Martin FG and it was 13-6.

With Matt Prater's third FG securing opening the 16-6 lead, Petty wasn't going to be able to duplicate his San Fran comeback from last year, but in the final 1:04, he tried, trying to find rookie TE Jordan Leggett in the end zone. Instead he found S Rolan Milligan for Jets QBs' first interception of the first two summer games. Petty finished 15-of-24 for 160 yards.

"Anytime you get in there you need to be excited — that's game tape," Petty said of his extended look. "So yeah, when they told me it was going to be a half, I was excited and ready to rock and roll."

3. Old Nemeses vs. the D
Two who have done in Jets defenses in the past, QB Matt Stafford and WR Marvin Jones, did it again to crown the first TD drive of the game, a picture-perfect 5-yard fade over Morris Claiborne to make it 10-0 on the second play of the second quarter. Stafford, who left the game after that play, now has six TD passes and no interceptions in five starts, regular and preseason, against the Jets.

One play is not indicative of how the Jets D played, but the Green & White were not nearly as sturdy as against the Titans. Stafford's TD drive moved down the field 11 plays and 78 yards, then backup Jake Rudock drove the hosts 87 yards on 15 offensive plays before the first-half-closing FG that made it 13-0.

4. Good Pressure
The Jets' pass rush, which produced eight sacks against the Titans, produced sack No. 9 in less than five full quarters when Demario Davis swooped in and dropped Matt Stafford for an 11-yard loss, which helped hold the Lions to only a Prater field goal on their short opening drive.

Then Josh Martin, who was flashing through the second quarter, had four tackles at the half, including a strip sack of Detroit backup Jake Rudock that the Lions recovered. A delayed blitz threw off Rudock in the third quarter and he threw an interception to LB Corey Lemonier. And Lemonier added a sack in the fourth quarter and another pressure that produced an incompletion, both against third QB Brad Kaaya.

5. The Returners Game
With Lucky Whitehead (foot) sidelined, the kick return job is up for grabs. Marcus Murphy, who didn't play last week, got lots of KO return chances in the first half and looked OK on three returns for 71 yards (but was ruled to have lost a fumble on a return that was wiped out by a Lions penalty). Frankie Hammond muffed  one punt, fair-caught another, and took a late kickoff 23 yards. Romar Morris had one punt return for 9 yards. And the competition continues into next Saturday's annual showdown with the Giants at MetLife Stadium.