Argentina's Lionel Messi and Brazil's Vinicius Júnior had frustrating nights in South American World Cup qualifying.
While Messi could not help his team avoid a 2-1 defeat at Paraguay, Vinicius Junior missed a second-half penalty as Brazil was held to a 1-1 draw at Venezuela on Thursday.
Argentina will remain on the top of the 10-team round robin competition with a 22 points in 11 matches, Brazil is provisionally in third place in the standings with 17 points.
Also on Thursday, Ecuador beat Bolivia 4-0. The Ecuadorians remain in fifth position with 16 points, while Bolivia is in eighth place with 12 points.
The 11th round of South American World Cup qualifying will continue on Friday with second-place Colombia visiting Uruguay and the bottom two teams in the standings, Peru and Chile, facing off in Lima.
Argentina played at Paraguay with the hosts having banned local fans from wearing any Messi shirts in the home crowd. TV footage of the match in Asuncion showed that the vast majority of the local crowd was wearing Paraguay's red and white colours, with no Messi shirts visible in the local broadcasts.
Messi had few opportunities to touch the ball during the first half, but saw Lautaro Martínez open the scoring in the 11th minute with a crossed shot. The goal was allowed after a video review.
Paraguay scored the equalizer with a bicycle kick by Antonio Sanabria in the 19th minute, shortly after defender Gustavo Gómez hit the bar with a header.
The hosts continued to apply pressure, and gave the Argentine star some heavy marking. Messi showed he was upset with Brazilian referee Anderson Daronco for not sending off Paraguay's Omar Alderete for his aggressive tackles.
It was Alderete who scored Paraguay's winner with a header in the 47th minute, which puts Paraguay back in contention for a spot in the next World Cup.
"We came to a hard place where the national team always struggled," said Martínez.
"We have to correct a lot of things we did wrong in this match, but generally speaking we are playing well. We are still in the lead, and we have to look forward."
Vinicius Júnior is still without a goal in six matches of World Cup qualifying.
He had the chance to score a potential winner after he earned the penalty in the 67th minute but his low spot kick was saved by goalkeeper Rafael Romo and the Brazil forward then shot wide from the rebound.
Brazil had the best chances in the first half, with Vinicius hitting the post once after dribbling three Venezuelans and shooting from the edge of the box. But it was Raphinha who opened the scoring from a free kick in the 43rd minute.
Venezuela brought on 21-year-old Telasco Segovia at half time and the substitution had an immediate effect as he equalized in the 46th minute with a powerful shot from the edge of the box.
Venezuela went down to 10 men in the 89th minute after Alexander Gonzalez was sent off for hitting both Gabriel Martinelli and Vinicius Júnior in the face.
The irrigation system then came on two minutes before the final whistle at the Monumental Stadium in the city of Maturin, 500 kilometers (310 miles) west of the capital Caracas, which angered Brazil players.
"When we don't win I leave the pitch a bit disappointed, we deserved to win this one," Raphinha said after the match.
"But it is an important point playing away, we are working hard to win the next one at home."
Ecuador beat Bolivia with goals by Enner Valencia (26th minute), Gonzalo Plata (28th and 49th) and Alan Minda (61st).