COSTA MESA, Calif. -- If you have a superstar quarterback you need (at least) one big, strong and smart receiver who can haul in the long ball.

The Los Angeles Chargers have "Big Mike" to fill that role ... as in Mike Williams. They call him Big Mike because he's all the above qualities rolled into one. He's 6-foot-4, 218 pounds (maybe less now that he cut off his dreadlocks) and has come up with some of the most wide-open, game-changing receptions of the season to date.

Look at this past Sunday's win over the Cleveland Browns, when Williams had two monster touchdown catches -- one for 48 yards, which gave the Chargers a 28-27 lead early in a wild fourth quarter and an earlier touchdown in which he danced all alone into the end zone after a 72-yard pass from Justin Herbert.

Add in a third-and-10 reception for a first down and a drawn pass interference call on a fourth down during a game-tying drive in the fourth quarter, which eventually led to the first of running back Austin Ekeler's two fourth-quarter touchdown runs (the one in which the Browns didn't carry him in the end zone), and "Big Mike" was big time.

Williams set a career-high with 165 yards receiving on eight receptions and was quick to compliment his emerging superstar quarterback, Herbert, who threw for 398 yards and four touchdown passes while rushing for another touchdown.

"We got to score every time we have the ball," Williams recalled Herbert saying in the huddle. "And we were like, 'Yeah, we got you.' ... Herbert brings leadership. A great quarterback. Poise."

Herbert's success is based on his ability to put the ball right on the money to a variety of pass-catchers -- Ekeler, receivers Keenan Allen and Jalen Guyton along with tight ends Jared Cook and Donald Parham Jr. And, of course, "Big Mike," who not only has helped Herbert become a prime MVP candidate but is setting himself up for a big payday when he becomes a free agent after the season.

Despite his big size and bigger production, Williams is not exactly the biggest talker, so during games he counts on Allen to keep him fired up. After one of Ekeler's fourth-quarter scores Sunday (not that one) Allen leaned over on the sideline bench and stared at Williams, who was sitting next to him.

"What?" Williams asked Allen.

"It don't mean nothin' without the dub," Allen said.

“Huh?" Williams responded.

Allen yelled back: "IT DON'T MEAN NOTHIN' WITHOUT THE DUB."

"For sure," Williams responded.

They got the dub, putting the Chargers at 4-1 and atop the AFC West heading into Sunday's game at the 4-1 Baltimore Ravens (1 p.m. ET, CBS).

Williams' success this season is not completely unexpected. He's shown flashes of it since being drafted with the No. 7 overall pick by the Chargers in 2017. After struggling with injuries as a rookie, Williams led the team with 10 touchdown catches in 2018 and had a 1,000-yard season in 2019. Last season he had 48 catches for 756 yards and five touchdown receptions.

But this year feels different. Herbert and Williams have connected on an almost surreal basis. He's caught 31 passes for 471 yards and six touchdowns (one more than last season). He's been a difference maker and on pace to shatter his previous career-highs in several categories.

"We've done a much better job of spreading it out and getting him [Williams] the ball," Herbert said. "Noticing that he's a matchup nightmare and what he has been built to do, that's not luck. He's worked hard and done a lot of work in the offseason. All those times we've thrown in the offseason are paying off."

Williams is a nightmare matchup. Imagine being a 5-10 safety and seeing the Incredible Hulk jump right over you.

"The guy's a fantastic receiver," Chargers coach Brandon Staley said. "He can beat you in the deep part of the field, he can beat you in the first or second level. He can move you throughout the formations and what you're seeing is a guy who, when you need a win, can. He can."

The chemistry between Williams and Herbert has only grown stronger every week. They'll need it Sunday against the Ravens, who have a red-hot quarterback of their own in Lamar Jackson, who led the Ravens to a 16-point come-from-behind victory over the Indianapolis Colts on Monday.

Williams didn't practice on Wednesday due to a knee injury but is expected to be fine for Sunday.

"We believe in him," Herbert said of Williams. "He is one of the best to do those jump ball-type plays."