The body of 37-year-old Engram Lamar Crenshaw, of Katy, was discovered on Sunday morning, following a party at Smith's ranch-style home in a suburb about 30 miles southwest of the city.
Smith said Wednesday he was cooperating with authorities as they investigate Crenshaw's death.
"I just want to lend out my prayers and my thoughts to Lamar's family," Smith said. "A tragic accident happened, and it's just a heart-felt type of thing. It's a thing that sinks in my heart."
Fort Bend County Sheriff's Capt. James Burger said Wednesday that he had no new information in the case. An autopsy was performed on Monday, and Burger expects results of toxicology tests to come back in about three weeks.
Smith said he could not comment further on the incident. No charges have been filed.
Crenshaw was not affiliated with the team. Smith practiced on Wednesday, as the Texans prepare to open the season against Indianapolis on Sunday.
"It's a tragic situation and we're just supporting him as an organization," Texans coach Gary Kubiak said. "It's difficult, but all we can do is try to help him work through it."
The 6-foot-4, 295-pound Smith is about to start his eighth season, and third with the Texans. He's started 31 of 32 games for Houston since signing with the team as a free agent before the 2009 season. Smith was originally a fifth-round pick by Arizona in the 2004 draft out of Oklahoma State.