Howard, who got doctor's clearance for contact work Monday, participated in about half of the practice before icing his ankle.
"Being still for like 23 weeks, when you start back doing contact stuff, you're going to have bumps and bruises, pains and aches," said Howard, who also had surgery on his left wrist in May. "I'm just fighting through it and making sure everything is OK."
There is no timetable set for Howard's first appearance in a game. Coach Rick Carlisle would like for Howard to get some playing time in the preseason, but the priority is to get him completely healthy.
"We're looking for steady progress, which we've seen, but there's no timetable," Carlisle said. "We're going to play this day by day and see where it goes. He's worked extremely hard. He had a very serious procedure. This was a positive sign today, but by no means is he ready to jump into games any time soon."
The Mavericks aren't sure when Howard will get to work for the first time with Shawn Marion, who was acquired this offseason to pair with Howard. Marion missed his second consecutive practice due to a sore right calf. He isn't expected to play in Thursday night's preseason game against the Detroit Pistons.
"We're at a point here now where we've just got to make sure we get them healthy," Carlisle said. "Shawn's isn't a serious situation, but it's something where we've got to be careful with."
Tim MacMahon covers the Mavericks for ESPNDallas.com. E-mail firstname.lastname@example.org.