FRISCO, Texas -- When Mike McCarthy was introduced as Dallas Cowboys coach on Jan. 8, 2020, Zack Martin and Travis Frederick were among the players in attendance inside Ford Center at The Star.

Their presence, as well as the presence of tackles Tyron Smith and La'el Collins, was a huge reason why McCarthy wanted the Cowboys job. Smith, Frederick and Martin had been All-Pros and seemingly were in their primes. Collins was an ascending player, coming off his best season in 2019.

McCarthy never saw them play a game together, and the offensive line has been mixed and matched more than some old-school Garanimals ever since.

When the Cowboys play the Los Angeles Chargers on Sunday (4:25 p.m. ET, CBS), they will employ their 10th different starting offensive line in 18 games under McCarthy and their 15th different unit when factoring in-game changes because of injuries.

Before the 2020 NFL draft, Frederick retired when he decided he could not play at the level he desired after dealing with the after effects of Guillain-Barré syndrome.

Smith, Martin and Collins have yet to play in a game together during McCarthy's 17-game tenure, and the earliest they could play in a game together will be Oct. 31 against the Minnesota Vikings with the NFL suspending Collins for five games for violating the league's substance abuse policy.

Martin missed the season-opening loss to the Tampa Bay Buccaneers because he was on the reserve/COVID-19 list but is expected to practice this week and play against the Chargers.

"It's a challenge," McCarthy said of dealing with a lack of continuity on the offensive line. "We all go through it. I've always paid attention to statistics and analytics, and it gives you some direction when you're trying to build a roster and how you're allocating snaps and so forth. Really, the health and continuity of your offensive line, if you look at it historically, equates to winning. That's something you pay attention to."

The lack of continuity is a hindrance.

"Just understanding matchups," Cowboys offensive coordinator Kellen Moore said. "There's really talented guys on the other side of the football, and we've got to be smart about what matchups defenses can create and hopefully put ourselves in the best position to be successful and avoid any unnecessary challenges."

As the Cowboys prepare for games without Collins, who missed every game in 2020 because of hip surgery, they have to figure out if they want to play their best five offensive linemen or keep players at their natural positions.

If they proceed with their best five, then Connor McGovern will remain at right guard and Martin will move to right tackle, where he started two games in 2020 before a calf injury ended his season. If they keep players at their natural positions, then either veteran Ty Nsekhe or Terence Steele, who started 14 games as an undrafted rookie in 2020, would play right tackle with Martin at his normal right guard spot.

The Cowboys have extra time to prepare for the Chargers, which is why McCarthy and Moore have not revealed their plans yet.

Is it fair to ask Martin to play right tackle with no practice time at the position in training camp and him coming off a 10-day absence?

"Zack can pretty much do anything. Zack's really talented," Moore said. "Obviously he's not done it a whole lot out there, but once we start digging into this game plan, we'll have to make the decision in the next couple of days. But we're very early on the Chargers information right now."

In the Cowboys' past three playoff seasons (all divisional-round losses), each of those teams had continuity up front on the line.

• In 2018, the Cowboys knew going into the season they would not have Frederick, and his replacement, Joe Looney, started every game at center. Smith started 13 games and Martin 14. Connor Williams and Xavier Su'a-Filo split the 16 games at left guard. That season, the Cowboys had five offensive players selected to the Pro Bowl and won a playoff game after winning the NFC East with a 10-6 record.

• In 2016, Smith and Jonathan Cooper started 13 games on the left side of the line with Frederick, Martin and Doug Free starting every game at center, right guard and right tackle. Dallas had six offensive players selected to the Pro Bowl and had the best record in the NFC (13-3).

• In 2014, Smith, Frederick and Martin did not miss a start. Ronald Leary started 15 games and Free started 11 before an injury sidelined him. The Cowboys had seven offensive players selected to the Pro Bowl, finished 12-4 and were a controversial call away from making it to the NFC Championship Game.

The 2021 season isn't even two games old and the Cowboys are already shuffling chairs on the offensive line.

"We're used to being flexible with our game plans, with our approach to things, being aware of whatever matchups may present themselves through this game," Moore said. "Hopefully we'll put ourselves in a good situation."