In last year's season opener against the Packers, left defensive end Ray McDonald played 100 percent of the 49ers' defensive snaps - 68 plays total.
McDonald again played extensively in Sunday's rematch. But perhaps signaling that there will be more relief this year for him and other front-line players, he played only 90 percent of the 62 defensive snaps, 56 total. The change was even more pronounced for right defensive end Justin Smith, who played 66 snaps in the 2012 game (97 percent) but 52 snaps in the rematch (84 percent).
What's more, a pair of nose tackles, Ian Williams and Glenn Dorsey, provided most of the relief at defensive end. Williams played 10 snaps (most of them at defensive end) while Dorsey was in on eight. Tony Jerod-Eddie played three snaps. (Demarcus Dobbs was suspended for the game while Will Tukuafu was not active; Dobbs' suspension ends today, which will means the 49ers will have to make a roster move).
The condition of the 49ers' front-line players became an issue at the end of last season when it turned out that three of the four starters - Smith, Aldon Smith and Ahmad Brooks - played with injuries during the playoffs and Super Bowl. None of those players saw much relief during the regular season, and San Francisco's defense dipped toward the end of the season.
Aldon Smith played 100 percent of the snaps on Sunday and finished with 1 ½ sacks. Brooks played 95 percent of the snaps.
Other snap counts of note:
* Last year, No. 3 cornerback Chris Culliver played 90 percent of the defensive snaps. His replacement, Nnamdi Asomugha, played 92 percent of the snaps on Sunday.
* Along with Aldon Smith, every member of the starting secondary played 100 percent of the defensive snaps. That includes rookie Eric Reid, who had a strong first performance.
* Kyle Williams was very much the team's No. 2 receiver. While Anquan Boldin played 78 percent of the team's 77 offensive snaps, Williams was in on 71 percent of the snaps. Marlon Moore played 16 snaps (21 percent) while Quinton Patton played four snaps (5 percent)
* Frank Gore played 66 snaps; Kendall Hunter was in for 11 snaps. Anthony Dixon did not appear on offense.
- Matt Barrows