Both injuries occurred during Monday night's game against the Steelers. Foster's ankle injury looked especially gruesome, and the move to IR was expected. Ijalana's injury was unknown at the time, and him walking off the field on his own power left Colts' fans with hopeful thoughts. Alas, he's gone for the season.
The loss of both of these players is a far bigger blow to the Colts than was the loss of MLB Gary Brackett and S Melvin Bullitt. While Brackett and Bullitt were both starters on the defense, Brackett's replacement Pat Angerer is actually playing better than Brackett was.
Bullitt's play left much to be desired as well, and his absence allows the development of Joe Lefeged and David Caldwell. On the other hand, Ijalana and Eric Foster both were primed to make big contributions this year, and their departure leaves the offensive and defensive lines very thin. Ijalana, though not yet inserted into the starting lineup, was progressing nicely, as evidenced by his play on Monday night at left tackle.
The fact that the Colts were confident in him at LT (as opposed to moving Linkenbach over) was very telling in terms of his progression. Him gone for the season puts a big hole in an already thin position in terms of quality depth. Backup G/C Mike Pollak is already starting in place of Ryan Diem, none of the other backups have shown promise.
Foster has been playing tremendously this season at DT, and is a big reason why the Colts defense has been so stout against the run. The Tampa Bay running game looked much better in the second half with Foster out (didn't hurt that the defense was gassed). With Fili Moala's status unknown, and Drake Nevis experiencing back problems, Antonio Johnson is the only healthy DT. Because of these depth problems, the Colts made several other moves on Wednesday, as was expected.
To offset the loss of Foster, DT Ricardo Mathews was activated from the practice squad, with LB Nate Triplett being released. The Colts also signed ex-Colts OT Michael Toudeze and six-year veteran OT Quinn Ojinnaka to bolster the offensive line depth. In other news, OG Jaimie Thomas, who's currently on IR, was suspended by the NFL for violating the substance abuse policy. More details are not currently available.