Smith (hamstring) didn't participate in Thursday's practice, Kelsey Conway of The Cincinnati Enquirer reports.
Smith was listed as a non-participant on Wednesday's estimated practice report, so the tight end's absence Thursday clouds his status for Sunday's game against the Titans. If Smith misses his second game in a row this weekend, Drew Sample and Mitchell Wilcox would once again be in line for added snaps as the Bengals' primary tight ends.