With Brett Hartmann coming off a serious knee injury and facing a suspension for violating the NFL’s substance-abuse policy, the Texans have signed veteran punter Donnie Jones.

Jones, who turns 32 in July, was with the St. Louis Rams the last five seasons and led the league with a 50-yard average in 2008, when he was a second-team All-NFL selection.

The salary-cap constrained Texans’ first veteran free-agent acquisition in 2012, he received a one-year contract worth $890,000, including a $65,000 signing bonus. Of the total, $540,000 counts against the cap.

Hartmann, a rookie free agent last fall, won the job after competing with veteran Brad Maynard in training camp but suffered a torn ACL in the Texans’ Dec. 6 game against Atlanta. He subsequently failed an off-season drug test, which will sideline him for the first three games he’s on the active roster.

Jones’ gross punting average in 2011 was 44.3, just behind Hartmann’s 44.4, but neither posted especially good net averages with Hartmann finishing 28th league-wide and Jones 31st.

Matt Turk, the NFL’s oldest player, returned to the Texans after Hartmann was hurt covering a punt and averaged 42.7 in the last four regular-season games, then 41.8 in the two playoff games. He’s currently an unsigned free agent.

After punting for Miami as a rookie in 2004, Jones spent two seasons with Seattle before joining the Rams. His career average is 45.3.

Texans in free agency:

* Re-signed – Arian Foster, RB; Chris Myers, C; Jonathan Weeks, C.

* Signed – Donnie Jones, P, from St. Louis.

* Lost – Mario Williams, DE, to Buffalo; Mike Briesel, OG, to Oakland; Joel Dreessen, TE, to Denver; Jason Allen, CB, to Cincinnati.

* Released/unsigned – Eric Winston, OT, signed with Kansas City; Lawrence Vickers, FB, signed with Dallas; Matt Leinart, QB; Neil Rackers, K; Derrick Ward, RB; Bryant Johnson, WR; Matt Turk, P; Damione Lewis, DT; Dominique Barber, S; Quintin Demps, S.