Henin sported black strapping on her lower right leg during the course of her predictably one-sided 6-0 6-4 victory over world number 83 Vera Dushevina on Centre Court.
The Belgian, who is no stranger to serious injuries, admitted she had been suffering from a new foot problem but said she did not expect her performances to diminish as a result.
Henin said: “I have started to get a little bit of tendonitis in my right foot which has been bothering me in the last few days but is not really affecting me.”
The Belgian wrapped up the first set in just 20 minutes and only had to break sweat briefly in the second when Dushevina managed to break back to level at 3-3.
A loss of concentration briefly threatened to extend the action when Henin went break point down as she served to round up the match.
But a netted forehand erased Dushevina’s chances and Henin wrapped up her victory with two solid first serves.
Elsewhere Serena Williams believes she needs to be more like her sister Venus if she is to triumph at Wimbledon this year.
Serena was far from her best but still managed to stay on course for a quarter-final collision with top seed Henin by claiming a place in the third round with a 7-6 (7-4) 6-3 success against Australia’s Alicia Molik.
“I’m playing well, but not great,” said Serena. I still need to improve parts of my game and I can do that in doubles with Venus tomorrow.”
Meanwhile Ana Ivanovic and Jelena Jankovic maintained the twin Serbian challenge on Wimbledon.
While sixth-seed Ivanovic dodged the showers in one of 21 first-round women’s singles matches held over from the first two days, compatriot Jankovic, the world number three, joined Justine Henin in the last 32.
Ivanovic secured a 6-0 7-6 (7-3) victory over Melinda Czink, of Hungary.
Jankovic, who has made an impressive transition to the grass-court season, made light of Slovakian Jarmila Gajdosova on the graveyard of seeds, court two, taking just 48 minutes to secure a 6-1 6-1 second-round victory before the rain returned.
Former champions Martina Hingis also beat the weather to secure a place in the last 32 but 10th seed Daniela Hantuchova, eighth seed Anna Chakvetadze and 15th seed Patty Schnyder were thwarted by the rain.
Hingis, having survived a scare at the hands of British teenager Naomi Cavaday on the opening day, enjoyed a smoother passage through to the third round with a 6-1 6-2 win over Aiko Nakamura, of Japan.
“I think the match was a lot closer than the score showed,” she said.
“I beat her like that the last time we played in Australia but it was definitely much more difficult today.”
Among the other delayed first-round ties, Russian 12th seed Elena Dementieva completed a ninth win in 11 meetings with Nathalie Dechy, of France, to secure a 6-2 7-6 (9-7) success.
France are still represented by Tatiana Golovin, Severine Bremond and Aravane Rezai, in addition to defending champion Amelie Mauresmo.
Martina Muller, of Germany, took just 41 minutes to beat Israel’s Anna Smashnova 6-0 6-0. The Israeli won just 17 points in the match.
Nicole Vaidisova, the 17-year-old 14th seed, disposed of Wimbledon debutant Karin Knapp, of Italy, and there were also first-round wins for 16-year-old Austrian Tamira Paszek and Italian trio Francesca Schiavone, Mara Santangelo and Tathiana Garbin.
Meanwhile, fourth-seed Mauresmo, who plays Yvonne Meusburger, of Austria, today, has withdrawn from the women’s doubles to avoid exacerbating a minor muscle strain and concentrate on her title defence.