Russia are on the brink of dropping out of the Davis Cup's World Group for the first time after going 0-2 down to Brazil on the first day of the competition here.
Brazil took the lead Friday when Russia's World No.96 Igor Andreev retired with a shoulder injury while 2-6, 1-6 down against Rogerio Dutra Silva, who is ranked 19 places below the Russian.
Brazil's 41st-ranked team leader Thomaz Bellucci faced stiff resistance at times from No.163 Teymuraz Gabashvili in Friday's second rubber, but eventually dispatched him 6-3, 4-6, 6-0, 7-6(4) to put Brazil within one win of taking Russia's place in the top-tier World Group.
"The important thing was to keep calm when I lost the second set. Then I started to play more aggressively," Bellucci said.
The decisive win could come in Saturday's only fixture, a doubles match between Brazil's highly-rated doubles specialists Marcelo Melo and Bruno Soares and the Russian pair of Alex Bogomolov Jr. and Stanislav Vovk, a surprise inclusion in the squad given his world ranking of 465.
Bellucci appealed for his team to keep their nerve despite the lure of a place in the World Group after losing at the playoff stage in each of the last six years.
"The fans can get very excited. We on the court have to remain calm. We have not won anything yet," he said.
Andreev warned that his shoulder injury, which he picked up earlier in the year, "looks very bad".
The injury could prevent him playing a potentially decisive match against Bellucci Sunday, he said, in which case Russia would be forced to field another player in his place.
The match is a replay of last year's playoff between Russia and Brazil, which the Russians won 3-2 on a hard court in Kazan.
This current tie is being played on clay in the Brazilian town of Sao Jose do Rio Preto.
If Brazil can reach the World Group, it would be the country's first appearance at the top level since 2003, when team included former World No.1 Gustavo Kuerten.