NASHVILLE, Tenn. — Taylor Heinicke's first snap in his debut NFL start was under adverse circumstances.

The Vikings were down seven points, lining up on the 6-yard line and on the road. The undrafted rookie calmly completed a 16-yarder to rookie Stefon Diggs for breathing room.

The drive, however, ended abruptly when Diggs fumbled while trying to fight for a first down on a third-down play in a 24-17 loss by the Vikings to the Titans in the preseason finale for both teams.

Heinicke received exclusive opportunities in the preseason finale and led a two-minute drive that resulted in a field goal before halftime. He built on that momentum with a touchdown drive to open the second half with help of a one-handed catch by running back Dominique Williams, who dedicated the play to his mom.

"His poise was tremendous," Williams said. "He didn't get too high or too low on anything. He stayed steady and went through his progressions. I'm not a quarterback expert, but he looked pretty good to me."

Heinicke said the snag Williams made in stride during the 14-yard touchdown "bailed me out right there" and added, "He's a good player. He's a playmaker."

Williams said it was a moment from practice transferring to a game.

"We do a lot of throws outside of the body in practice so kind of get used to catching with one hand, but Taylor's throw was kind of a surprise," Williams said. I didn't know it was coming to me until it got on me."

The offense was threatening late with another two-minute drill, but Heinicke was sacked after a penalty erased a fourth-down completion to Diggs, who had eight catches for 85 yards.

"I thought I did pretty well, but there's a lot of plays I feel like I left out on the field that could have been executed better, a lot of deep balls I can work on," Heinicke said. "A loss is a loss, and those plays might affect the outcome between a win and a loss so tomorrow I've got to try to work on those things."

Heinicke finished 27-of-41 passing (65.9 percent) for 279 yards with two touchdowns and no interceptions for a passer rating of 101.6 on a night when Teddy Bridgewater and veteran backup Shaun Hill were shelved along with every other first teamer on offense.

A frequent question to Heinicke and Vikings Head Coach Mike Zimmer has been whether the team will keep a third quarterback as they reduce the roster from 75 players to 53 by 3 p.m. Saturday.

"That's not in my hands. That's their decision, but I've had a great ride from OTAs until now, have learned a lot," Heinicke said. "I think I've grown as a quarterback. I hope to be here and want to be here and keep learning from Teddy and Shaun and (quarterbacks coach) Scott (Turner) and (Offensive Coordinator) Norv (Turner). I think they're the best in the business, so hopefully I'm here for that and continue to be on the Vikings."

Heinicke finished the preseason 57-of-82 passing for 516 yards and a passer rating of 89.3.

Zimmer didn't like the hits that Heinicke took, including two sacks, but said the QB showed toughness.

"He's a tough kid," Zimmer said. "He hung in there, he got back, he had good control of the offense and made some good throws. There were some good throws in the two-minute drill at the end. There were a lot of things that happened over the course of the game that showed he's got something to him."

When asked about the potential of keeping a third QB on Thursday night, Zimmer said "We'll figure all that out this week."

Day of rest, opportunity for growth

The Vikings opted to start Gerald Hodges Jr. at middle linebacker for the second straight week. Aside from Hodges, Robert Blanton was the only other first-teamer (on the non-official depth chart) to start.

The Vikings decision to not play a total of 29 players created opportunities for younger players.

Antone Exum Jr. led the Vikings with six tackles (press box tally), followed by Brandon Watts, Edmond Robinson and Chigbo Anunoby with five apiece.

Watts and Scott Crichton each had sacks, and Crichton also was credited with a pass defensed.  

Pruitt back in action

Rookie tight end MyCole Pruitt returned to action for the first time since suffering an injury Aug. 15.

"It definitely felt good," Pruitt said. "It was a couple of bumps in the road, but it felt good to get back out there and get my feet back under me."

Pruitt had three catches for 41 yards, including a 28-yarder during the two-minute drive in the first half. He said he was impressed by Heinicke as well.

"It was the first time he was able to play a whole game, and I think he did pretty well under the circumstances," Pruitt said.

Flipping tackles

The Vikings opted to play rookie Austin Shepherd at left tackle and second-year pro David Yankey at right tackle for the first time this preseason. Both started, and Shepherd said he tried to show versatility.

"It was pretty good, just different being on the left side. I've never really played on the left side in my life, so the two days of practice really helped. I felt pretty good over there.

"I've played right tackle, right guard and left guard," Shepherd said. "They wanted to try me at left tackle, so I'm pretty much trying to give them a reason to not cut me."

The Vikings plan to start Matt Kalil at left tackle and rookie T.J. Clemmings at right tackle, but likely want to identify an option for a backup to be active on game days.

Hustle play

Michael Mauti received a robust welcome back to the sidelines by the linebackers group after he blocked a punt and recovered the ball at the Tennessee 26-yard line. Heinicke hit Diggs for a 7-yard touchdown three plays later to make it 24-17 with 3:54 left in the game.

"They just kind of failed to set a little bit and it was something I've been working on a couple of weeks in preseason and practice and it kind of opened up for me," Mauti said. "It's just one of those things. I kind of needed it, in the fourth preseason game, it's one of those plays that keep guys around. I know they've got some tough decisions to make this weekend, so hopefully that helps out."

The road ahead

The Vikings open the regular season at the 49ers on Sept. 14 on Monday Night Football.

"We're never going to stop working," Zimmer said. "I think that our guys feel good about … training camp. I think they feel good about the effort they've given and about the preseason. I'll probably feel a little better after tomorrow than I do tonight.

"This team has a chance if we'll figure it out. You don't want to lose. You'd rather lose a preseason game. There's some things that we can correct from tonight's game. … It's probably a good eye-opener for these guys."