SAN DIEGO – With the San Diego Chargers set to open training camp in less than two weeks, I will take a closer look at some of the question marks the team must answer leading up to the regular season.

During the offseason, Chargers general manager Tom Telesco made some minor tweaks to an offensive line that underperformed last year, leaving the group mostly intact.

San Diego drafted USC product Max Tuerk in the third round and signed veteran Matt Slauson, adding much-needed depth and talent to the center position. But when the Chargers begin the regular season, four of the five projected starters will be the same as in 2015.

King Dunlap was one of the best pass protectors in the game during the 2014 season. AP Photo/Bill Wippert

Left tackle King Dunlap and left guard Orlando Franklin played a combined six games together last year.

Dunlap and Franklin could not stay on the field for any length of time in 2015, and that instability on the left side of the line significantly impacted the play of San Diego’s entire offense.

However, the Chargers believe Dunlap can return to the type of player he showed in 2014, when he played at a Pro Bowl level according to quarterback Philip Rivers.

Offensive coordinator Ken Whisenhunt saw a player in Dunlap with renewed energy during the offseason. The Chargers will need Dunlap to play at a high level in order for the offensive line to jell.

“I look at the tape -- and I know he missed some games last year -- but I see a lot of what I saw from him in 2013,” Whisenhunt said at the end of San Diego’s mandatory minicamp. “He’s had a good week of practice, staying low and with good technique and working hard. I see energy from King and staying upbeat, which I like.

“I think he and Orlando are developing a relationship there. And I think Slauson has really helped from a standpoint of a guy that’s played in the league, and communicates well with that group. And it kind of goes out from there -- when you’ve got a quarterback and a center that work it well together in how they identify and communicate, it kind of spreads out.”

Whisenhunt said one of the things that helped to build chemistry along the offensive line was going against John Pagano’s defense with multiple looks during the offseason, which forces the guys up front to quickly identify the front and how to block them.

At 6-foot-9 and 330 pounds, the 30-year-old Dunlap has the talent to be a productive blindside protector in the NFL. Dunlap had his best season in 2014, playing a full, 16-game season for the only time in his eight-year NFL career. Dunlap played 1,000 snaps, giving up just three sacks on 625 passing plays, according to Pro Football Focus.

The Chargers rewarded Dunlap with a four-year, $28 million deal. But in 2015, Dunlap missed nine games due to concussion and ankle issues. He played just 294 snaps last season.

Because of his injury history, the Chargers restructured Dunlap’s contract during the offseason, with his $3.3 million base salary in 2016 fully guaranteed, but no money guaranteed beyond 2016.

For his part, Dunlap said he’s committed to staying on the field in 2016. If Dunlap can return to the performance he put on tape in 2014, the Chargers should be much more consistent along the offensive line in 2016.

“Last year sucked,” Dunlap told the team’s website. “It was awful with all the injuries. Personally, I felt like I let a lot of people down missing all the games I did. I let the whole team down. The goal for me this year is to be healthy and stay healthy.”