INGLEWOOD, Calif. >> With Cooper Kupp sidelined by a hamstring injury, Puka Nacua is picking up the slack for the Los Angeles Rams.

So far, so record-breaking good.

Nacua, a fifth-round pick out of BYU, set the NFL single-game record for most receptions by a rookie with 15 catches for 147 yards in Sunday’s 30-23 loss to the San Francisco 49ers.

“I don’t know if I can wrap my head all the way around it,” Nacua said. “I’m executing in the moments where I’m asked and try to stay as present as I can.”

Nacua broke the record with a 17-yard reception late in the fourth quarter that put the Rams in the red zone and set up a 38-yard field goal by Brett Maher on the game’s final play.

The reception surpassed the former mark of 14 held by Washington’s Roy Helu, the New York Giants’ Saquon Barkley and Pittsburgh’s Najee Harris.

Nacua is also the first player in NFL history with double-digit receptions and 100 yards receiving in each of his first two career games. He had 10 receptions for 119 yards in last weekend’s opener at Seattle.

He is the fifth player overall to accomplish the feat in the first two games of a season. Isaac Bruce (1998) and Kupp (2022) also did it with the Rams, along with Atlanta’s Andre Rison (1994) and Miles Austin with Dallas in 2010.

Nacua was questionable going into Sunday’s game after he missed practice on Thursday due to rib and oblique injuries on his right side. Despite being less than 100 percent, he was targeted 20 times and averaged 9.8 yards per catch.

“Every time I turned to look, (Nacua) was catching a ball and falling forward with two guys on him,” said 49ers linebacker Fred Warner, a fellow BYU product. “He did a great job.”

Nacua’s longest reception was a 20-yarder on a second-quarter drive that ended with Kyren Williams’ 6-yard TD catch, tying it at 10. Nacua ran a drive route on third-and-4, and he was able to get separation before he was pushed out of bounds at San Francisco’s 34-yard line.

Nacua also had a 9-yard catch on a fourth-down play in the fourth quarter to keep a drive alive.

“I thought he played great. He is winning his matchup, doing a great job of separating and catching the ball,” said Matthew Stafford, who was 34 of 55 for 307 yards and a touchdown with two interceptions. “If we’re in zone, I’m just clicking through progressions. He’s on the front side of a few of them and doing a nice job getting catches.”

Nacua’s 25 receptions are also an overall league mark for a rookie in his first two games. The previous mark was 19 by San Francisco’s Earl Cooper in 1980.

He is also the fourth player with at least 100 yards receiving in his first two games, with the last being Will Fuller in 2016 with Houston.

Besides Nacua, only New Orleans’ Michael Thomas and Rison have had at least 25 catches in his team’s first two games of a season.

“I feel like I’m doing my job when (Stafford) throws the ball my way. It’s my job to come down with it and he always makes it super easy,” Nacua said.

With Kupp on injured reserve and not able to be activated until Week 5, Nacua will remain a prime target for Stafford.

“The game makes sense to him. Physically and mentally he’s tough and works hard,” Rams coach Sean McVay said. “He’s got great guys to be able to lean on. I think Puka is going to continue to improve. I love Puka.”