Initially completing a single lap ergonomics check, Holdsworth handed over to Reindler before returning for a final five-lap run.
The shakedown was run in dry conditions despite rain earlier in the morning.
It was the first track time for Holdsworth since he fractured his pelvis and two ribs and damaged ligaments in his knee in a sickening crash at Hidden Valley in June.
“The plan was to build up to it over the five laps, but straight away I felt good enough to be on the pace,” Holdsworth told Speedcafe.com.
“There's a little bit of rib pain but as far as the pelvis and the knee go, it's perfect. I'm very happy with the way my body handled it.
“It's given me a lot of confidence in my body ahead of Sandown.”
Running without any extra protective gear today, Holdsworth admits he'll need padding around his affected ribs before returning to the wheel for more laps during practice at SMP this Friday.
“I wanted to try it out how I'd normally run today get a feel for what we need to do for this weekend and especially for the race at Sandown,” he said.
“That was the main aim, to see what needs attention on my body in the lead-up to Sandown so I don't have any issues in the race.
“At the moment the pain in the ribs is probably the thing that we need to address, but I'm sure a bit of padding and a few pain killers will do the trick. That was to be expected.
“The main thing was the pelvis. I've been walking on my right leg now for three or four weeks, but I've only just gotten off the crutches on Friday and started putting full load through my left leg.
“It's only had a couple of days for the muscle to get used to it and feel normal again. It's all come back pretty quickly which I'm very pleased about.”
Holdsworth has already received clearance from his specialist to drive in practice this weekend and race at Sandown.
He been assured that he is not at risk of doing further damage to the injuries should he have another accident at either venue.
“I've been told that it would take another impact of the same size to do that damage again,” he said.
He's also shrugged off any suggestion that his seating position within the Team 18 Holden contributed to his injuries.
At 170cm, Holdsworth is the second smallest driver in the field, ensuring he must sit higher in the control seat than the bulk of his rivals.
“We're looking into how we can get me a little bit lower in the seat, but I don't think it contributed to it to be honest,” he said.
“I'd like to get more protection around the knees, which is what Supercars is looking into. That's the main thing for me.
“At the end of the day even if I was wrapped in cotton wool, when you have a 95g impact you're going to sustain pretty horrific injuries.”
DJR Team Penske is expected to debut a new driver protection tray during the enduros, which will also be made available to other teams.
The tray has been developed with Penske's NASCAR expertise and is designed primarily to restrict unwanted leg movement in the event of an accident.