NASHVILLE, Tenn. -- Go back to Week 6. The Tennessee Titans were coming off two losses in which the offense scored a total of seven points. Through the first six weeks of the season, the Titans' red zone offense was ranked 19th in the NFL after scoring touchdowns on 53% of its trips inside the opponent's 20-yard line.

Things changed after the Titans named Ryan Tannehill the starting quarterback for Week 7.

Four games later, Tannehill has led the Titans to the top spot in the league in red zone offense, scoring touchdowns on all 10 red zone trips. For the season, the Titans have scored touchdowns on 72% of their red zone trips.

Part of their recent success can be chalked up to greater confidence.

"Just that belief that we are going to get into the end zone," Tannehill said after Tennessee's 27-23 win over the Buccaneers on Oct. 27. "When we get down there, we believe that we are going to get into the end zone."

Added Titans quarterbacks coach Pat O'Hara, "Ryan has an undying belief that we are going to score every time we get down there, and he should. Every quarterback should. We started working hard on our red zone efficiency in the spring. It's paying dividends now."

Titans coach Mike Vrabel acknowledged the team's red zone confidence and said it's the quarterback's job to "raise everybody's level of performance."

In the first six weeks, the offense was settling for field goals when it reached the red zone. In Marcus Mariota's six starts, the Titans averaged 1.3 touchdowns in 2.5 red zone visits per game. Mariota's red zone QBR was 17.0, according to ESPN Stats & Information.

In the past four games under Tannehill, Tennessee has averaged 1.8 touchdowns in the same amount of visits. Tannehill's red zone QBR is 97.1. Additionally, Tannehill's completion percentage in the red zone is 70.6%, compared to Mariota's 46.2%.

Other factors Vrabel cited as contributing to the team's success include improved pass protection and Tannehill's quicker release. Defenses have not been able to get as much pressure on Tannehill in the red zone. He has been under pressure on only 19% of his dropbacks, whereas Mariota was under pressure on an NFL-high 58.8% of his dropbacks.

The windows in the red zone open and close more quickly. Quarterbacks need to anticipate the window opening and pull the trigger in enough time to fit the ball in. Tannehill's pass to Adam Humphries in the end zone against the Chiefs for a 23-yard touchdown on Nov. 10 is an example of an on-time, tight-window throw.

Although the pass came from the 23-yard line, just outside the red zone, Tannehill trusted Humphries to beat his man and get to the spot against the two-man coverage the Chiefs' defense was playing. Being a reliable option for the quarterback is why the Titans made Humphries a priority in free agency.

"Everybody has their own traits as a receiver," Humphries said. "For me, it's just being on the same page as the quarterback. Being in the right spot at the right time. You have to separate for just a split second and get open."

The connection between Tannehill and Humphries has heated up recently. Humphries has caught 12 of 15 targets from Tannehill for 152 yards. His only touchdown this season was the winner against the Chiefs. Given Humphries' short-area quickness, he should be a key player for the Titans, especially in the red zone, where the field is condensed.

The Titans are 3-1 since Tannehill took over as the starter, and their playoff hopes might rest on keeping their red zone progress going in the season's final six games, when they play four games against AFC South opponents, including the Texans twice.

"Hopefully, we can get down there more and continue to score, but that’s been something that’s been really positive for us," Vrabel said.