According to NFL Network's Ian Rapoport, Gould's availability is "very much in doubt" for the home game due to a strained quad, and the Niners have signed free-agent kicker Chase McLaughlin in case Gould can't go.
Rapoport added that a source said Gould's injury is "not serious" and "not considered long-term."
The Niners will put their perfect 8-0 record on the line Monday when they host the 7-2 Seahawks at Levi's Stadium.
The 36-year-old Gould is in the midst of his third season with the Niners and his 15th in the NFL. Through eight games this year, Gould is struggling to the tune of 13-for-20 (65 percent) on field goals, although he has made all 26 of his extra-point attempts.
The former longtime Chicago Bears kicker is coming off two dominant seasons for the 49ers, as he went 39-of-41 (95.1 percent) on field goals in 2017 and 33-of-34 (97.1 percent) last season. Those marked the two most accurate seasons of his career in years that saw him appear in at least 11 games.
Even with this season's struggles factored in, Gould is the fourth-most accurate kicker in NFL history behind only Justin Tucker, Josh Lambo and Stephen Gostkowski with a career field-goal percentage of 86.7 percent.
In McLaughlin, the 49ers signed a far less experienced kicker, although the 23-year-old did appear in four games for the Los Angeles Chargers this season as a fill-in. In those games, McLaughlin went 6-of-9 (66.7 percent) on field goals and 7-of-7 on extra points.
McLaughlin is an undrafted rookie out of Illinois who spent the preseason with the Buffalo Bills. He turned some heads by making all three of his preseason field-goal attempts, including a 54-yarder.
Monday's game figures to be a tightly contested affair since the Niners and Seahawks are two of the top teams in the NFL, which means kicking could be the deciding factor.
For Seattle, Jason Myers, who made the Pro Bowl with the New York Jets last season, is just 12-of-17 (70.6 percent) on field goals and 24-of-26 (92.3 percent) on extra points this season, so the Seahawks may not have much of an advantage in that department even if San Francisco is forced to turn to McLaughlin.