Jacobs (ankle) didn't practice Wednesday, Paul Gutierrez of ESPN.com reports.
Earlier this week, coach Jon Gruden was pessimistic about Jacobs' chances of suiting up Sunday against the Colts, and not much seems to have changed on that front. If Jacobs is forced to miss a second consecutive game this weekend, Devontae Booker would be in line to headline Las Vegas' backfield again, with Jalen Richard and Theo Riddick also on hand to provide support.