OWINGS MILLS, Md. — Despite optimism regarding the treatment and rehabilitation he received for his injured toe on Friday, it appears Ben Grubbs will be unavailable to the Ravens on Sunday. The starting left guard missed his third straight practice on Friday and is listed as doubtful for the Ravens’ Week 2 matchup with the Tennessee Titans. Earlier in the day, coach John Harbaugh labeled Grubbs as a game-time decision, but it’s likely the fifth-year lineman will miss the first game of his NFL career. “Even though it’s a small part of your body, it’s a huge part in running around, pushing off, and blocking, especially for my position,” Grubbs said prior to the release of Friday’s injury report. “It’s my first time experiencing this, so I don’t really know what to expect. You just hope that, God willing, I’ll be able to play.” Veteran backup center Andre Gurode will likely start in Grubbs’ place at left guard. The 10th-year veteran started 28 games at guard in 2003 and 2004 before being switched to center where he earned five Pro Bowl selections for the Cowboys. The Ravens will also be undermanned in the secondary as both Jimmy Smith and Chris