Jeremy Johnson Nick Marshall Tennessee

Auburn quarterback Jeremy Johnson (6) and Auburn quarterback Nick Marshall (14) lead the Tigers onto the field before the Tennessee game Saturday, Nov. 9, 2013, at Neyland Stadium in Knoxville, Tenn. (Julie Bennett/jbennett@al.com)

AUBURN, Alabama -- Gus Malzahn wanted to build and develop depth during the spring, and in some spots Auburn succeeded.

Auburn not only re-tooled some positions and added some new weapons, they strengthened a few more good options as backups. The question is whether Auburn has completely silenced their concerns after an injury-plagued spring on defense.

With that in mind, here are the five positions Auburn fans and coaches should have more confidence in as the Tigers enter the summer months:

1. Quarterback

Auburn returns two quarterbacks who not only started games, but excelled. Nick Marshall returns as possibly the SEC's best quarterback, and does so as the first second-year starter ever under Gus Malzahn. Marshall worked to get better as a passer in the spring and it showed in the spring game, when he was patient with his progressions and made quick, sharp decisions and throws.

Offensive coordinator Rhett Lashlee wants Marshall to complete 65 to 70 percent of his passes in 2014, which would be quite the upgrade from the 59 percent he hit in 2013. If he hits that number, Auburn's offense could prove more potent -- and balanced -- than the run-heavy version we saw develop late in the 2013 season.

Fans shouldn't forget about Jeremy Johnson either. He didn't have a great A-Day spring game, but he proved himself when presented with major playing time in two games in 2013. He provides a different threat at quarterback, where his big arm will come into play in 2015 and beyond -- if not sooner if Marshall gets hurt.

2. Receivers

Auburn wide receiver D'haquille Williams (1) dodges Auburn defensive back Mack VanGorder (12) during the first half of the A-Day game Saturday, April 19, 2014, at Jordan-Hare Stadium in Auburn, Ala. (Julie Bennett/jbennett@al.com)

This pick was a hard one to make after an up-and-down season in 2013, but the Tigers sure do seem deep at the position. The Tigers return their best receivers from last season and add D'haquille Williams, whose presence was felt immediately at the A-Day game with five catches for 88 yards and an acrobatic, 3-yard touchdown grab on a fade route. Newcomer Stanton Truitt, a freshman who enrolled in January, could also see the field earlier than some project.

The addition of Williams could also help guys like Quan Bray, who got lost at times in the offense in 2013, with an additional threat on the outside opening receivers on the inside. Defenses can no longer focus on stopping Sammie Coates, too, which will open things up for Williams and others in 2014.

The best news of all for the Tigers? Dropped passes were not as common in the spring as they were in 2013, when it seemed the Tigers were assured of at least one big drop in every game, including the 2014 BCS National Championship.

3. Running back

Auburn running back Corey Grant (20) outruns Tennessee defensive back Cameron Sutton (23) during the fourth quarter Saturday, Nov. 9, 2013, at Neyland Stadium in Knoxville, Tenn. (Julie Bennett/jbennett@al.com

The battle for the starting job at running back will be waged through August and potentially through the first three or four games of the season. The Tigers have options with seniors Cameron Artis-Payne and Corey Grant, but the injury to Peyton Barber in the spring game was not a good omen for the redshirt freshman as he attempts to stay a step ahead of incoming freshman Roc Thomas, a five-star talent out of Oxford.

Auburn has options if a starter fails to emerge early, which means Gus Malzahn could use a tailback-by-committee approach as he has done in the past. Artis-Payne can be a potential bruiser between the tackles if he does not hesitate at the point of attack. Grant is a speedster, and proved it once again with his 128 yards on five carries in the spring game, but can he absorb contact and pick up yards after a linebacker hits him? Those are questions that may not be properly answered until the fall, when Thomas and Barber could still emerge as the go-to guy.

4. Defensive tackle

Auburn defensive lineman Gabe Wright (90) works out during Auburn's first spring practice Tuesday, March 18, 2014, at the Auburn Athletic Complex in Auburn, Ala. (Julie Bennett/jbennett@al.com)

Four key contributors return from last season, and there's an opportunity for them to step up again while also developing depth with three newcomers, including junior college transfers DaVonte Lambert and Devaroe Lawrence. Injuries proved problematic for the defensive line in the spring and tackles Gabe Wright and Montravius Adams had to move outside to fill spots at defensive end.

Defensive line coach Rodney Garner has to feel good about the pieces he has in place, and the possibility of creating a push in the middle of the field rather than depending on a pass rusher like Dee Ford or Carl Lawson off the edge as he did last season. How quickly Lambert, a former Tennessee commitment, develops will be important for the defensive line in 2014.

5. Safety

Auburn safety Jermaine Whitehead (9) celebrates after an interception during the 2013 SEC Football Championship between Auburn and Missouri at the Georgia Dome in Atlanta, Georgia on Saturday, December 7, 2013. (Julie Bennett@al.com/al.com)

The Tigers return their three most important pieces on defense -- safeties Josh Holsey and Jermaine Whitehead, and Star Robenson Therezie -- and get some much-needed help with the return of Justin Garrett at the hybrid Star position. Garrett was projected to be the breakout star during Ellis Johnson's first season on campus but foot injuries limited him to two games in 2013.

The Tigers should be OK at the safety positions if they stay healthy. Holsey tore an anterior cruciate ligament in October and did not participate in contact drills during spring practices as coaches continued to exercise caution with his knee.

Auburn is also not short on options with nine players -- seven upperclassmen -- capable of seeing time this season in at least one of the three positions. Garrett is the most versatile of the bunch and could see time at Dime, Star safety and weakside linebacker.