Old Mill running back Rob Chesson had one of his favorite performances of the season against Arundel on Oct. 6. (Jonathan Newton/WASHINGTON POST)

Old Mill’s Rob Chesson stood on the sideline of last Friday’s Maryland 4A football semifinal, thinking his work was likely finished for the night. The senior running back had already piled up more than 300 yards and six touchdowns to help the third-ranked Patriots to a 28-point lead over Catonsville.

As they neared the end zone again, Chessonre-entered the game on fourth and goal. After serving as a decoy on a pass play that drew pass interference, Chesson stayed in the game and scored standing up on a six-yard run for his 49th touchdown of the season, a state record, to punctuate an eventual 49-20 win.

“That’s my job,” Chesson said. “We worked so hard to get it down there, we wanted to make sure we punched it in.”

No player in the Washington area has been as adept at finding the end zone as Chesson this season. By averaging nearly four scores per game, the 5-foot-10, 170-pound back, who also has an area-best 2,549 rushing yards, has carved out his place in Maryland history.

With 48 rushing touchdowns and one punt return score, he has blown past the previous single-season state record of 43, which was set in 2007 by Wicomico’s David Brown. Monticello’s Takeem Hedgeman holds the Virginia High School League record with 51 touchdowns in 2007, but no local Virginia player has scored more than 40 touchdowns in a season, according to the VHSL record book.

Chesson will lead No. 3 Old Mill (13-0) against No. 2 Quince Orchard (13-0) on Friday in the Maryland 4A final at M&T Bank Stadium. The Patriots are seeking their second state title in three years and first perfect season in school history.

“He’s a kid that is determined to score the football,” Old Mill Coach Chad McCormick said. “He’s not the biggest guy in the world, but he’s become so durable. He can run inside and outside, and it’s his physical conditioning that has allowed him to get so many carries throughout the year.”

Chesson has made the most of his first opportunity to carry the load for the Patriots. McCormick said he believes Chesson was talented enough to start as a sophomore when the Millersville school won its first state title, but he played sparingly behind a pair of Division I prospects, Josh Furman and Jason Clements. Last season, Chesson scored 25 total touchdowns — including eight on special teams — but he split carries with Navy-bound Demond Brown.

McCormick worried when the Patriots struggled in the red zone during August scrimmages, but Chesson quickly erased those doubts and kept getting better as the season progressed. As a result, Old Mill has been dominant this fall, outscoring opponents, 541-106.

Buoyed by an improving offensive line, Chesson has rushed for at least 200 yards in eight of his past nine games. In that span, he has averaged 230 rushing yards per game with 37 total touchdowns. With the recent surge, he topped Ryan Callahan’s school record for rushing yards in a season.

Arundel Coach Chuck Markiewicz, a fixture on Anne Arundel County sidelines since the early 1970s, places Chesson among the top five running backs he’s coached against.

Markiewicz said Chesson’s ability to cut and accelerate in space — turning short runs into explosive plays — is what makes him special. Chesson has shown the ability to score from anywhere on the field with 21 touchdowns of 20 yards or longer.

“Everybody says the knock on him is he’s not fast, but if you don’t get two people on him on the second level, he’s going to be tough to catch,” Markiewicz said. “When he gets into the secondary, it’s over. That’s demoralizing for a defense.”

Chesson’s favorite performance of the season came in a 47-10 win over Arundel, coached by Markiewicz, on Oct. 6. In that game, Chesson lost the football trying to take a handoff from senior quarterback Deonte Shields on Old Mill’s first offensive play but rebounded to finish with 216 rushing yards and five touchdowns on a season-high tying 35 carries.

“We love to block for him,” senior wide receiver Torie Wagner said. “We know all we’ve really got to do is put it in his hands, and he’s going to give us 110 percent every down, every play.”

Despite those glowing reviews and eye-catching stats, Chesson has struggled to impress college recruiters. Rated a three-star recruit by Rivals.com, his only scholarship offers came from Buffalo and Towson before the season.

But Chesson said he will focus on what he can control, adding that the final goal he hasn’t checked off his mental list — a state title — remains the most important.

“There’s more to come,” Chesson said. “I set a high standard, but that don’t mean anything. Even though a lot of great things have happened, I’ve still got to stay focused and play the game of football.”