The 40-year-old Barrichello started in the middle of the 34-car grid and stayed there during most of the race until a blown right-rear tire near the near of the race forced him to make an unscheduled pit stop.
"It was a shame I wasn't able to score some points," Barrichello said. "But everybody knew it wasn't going to be easy. The result was horrible, but there's nothing we can do about it now. It's important that at least I'm enjoying it all."
Barrichello is competing in Brazil again after more than two decades racing abroad. He ended his F1 career two years ago and couldn't secure a seat for a second season in the IndyCar Series in 2012.
"This is a new phase, I'm starting from scratch," Barrichello said. "We were super careful going into this race, just trying to survive. We were not too aggressive and the goal was to improve during the race, but it was difficult."
Barrichello was fastest in one of the practices before Sunday's race and had the 14th-fastest time in qualifying. But he was penalized after race stewards said he got in the way of another driver during the session, having to start three spots back on the grid.
"I tried to move forward in the beginning of the race but my car started getting loose, then the tire finally gave up in the end," he said.
Barrichello drove three races as a guest in the stock car series last season, finishing no better than 22nd.
The Brazilian hasn't ruled out racing in events such as the 24 Hours of Le Mans or the 24 Hours of Daytona, but he is not thinking about leaving the country again to race in other series. He has always said he planned to retire from racing in the local stock car series, Brazil's most popular.
Caca Bueno, a five-time champion in the series, won the season-opening race at Interlagos. The 12-race season will end in December.
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