South America Results: Nobby nets again in Peru
Ecuadorean champions Deportivo Quito lost 4-0 to local rivals LDU in a game they had threatened to boycott over a pay dispute.
Melgar snatched a point in amazing circumstances after drawing 1-1 away to newly-promoted Inti Gas.
The hosts, who had Jean Tragodara sent off after only nine minutes for a rough challenge, appeared set for their first win of the season when Mario Velarde scored from a free kick in the 88th minute.
The referee was surrounded by a furious Melgar team and media reports said one player appeared to push one of the policemen who came onto the field to protect the official.
Melgar coach Claudio Techara was sent off and his team at one stage threatened to abandon the match as play was held up for five minutes.
When the game re-started, Inti Gas lost concentration and Gerardo Gerarte equalised in the seventh minute of injury time after being left completed unmarked.
Former Newcastle United, Aston Villa, West Ham United and Boca Juniors midfielder Nolberto Solano converted a last minute penalty to give Universitario a 1-1 draw at Cienciano, who went ahead with a Mauricio Romero penalty after half an hour.
Paraguayan striker Richard Estigarriba scored four goals in Total Chalaco's 4-0 win over Jose Galvez.
Titleholders Deportivo Quito, who agreed to face LDU after being paid outstanding wages on Friday, crashed to a 4-0 defeat.
Walter Calderon and Argentine Claudio Bieler put LDU, the reigning South American champions, 2-0 ahead in only five minutes and Bieler added a third before halftime.
Deportivo defender Giovanni Caicedo put through his own goal in the second half.
Guayaquil rivals Emelec and Barcelona both remained winless after five games of the 2009 championship following their 0-0 draw in the Shipyard derby at the Capwell stadium.
Emelec are bottom after picking up their first point while Barcelona have four points, all from draws, under former Real Madrid coach Benito Toro.
Tolima's match at home to Atletico Nacional was interrupted early on when visiting fans clashed with fans outside the stadium and the wind blew tear gas across the pitch.
Several players were treated before play resumed.
Sergio Galvan gave Atletico a halftime lead but Tolima, who nearly pulled out of the championship because of chronic financial problems, replied with second-half goals from Rodrigo Marangoni and Wílder Medina.
The defeat left Atletico, one of Colombia's most popular clubs, bottom of the Apertura championship after losing all five games under former Ecuador coach Luis Fernando Suarez.
Titleholders America lost 1-0 to arch-rivals Deportivo Cali, where Andres Perez scored the only goal from a free kick after 20 minutes.
Atletico Junior are top with 11 points after beating Pasto 2-0 although the leadership is symbolic as eight teams qualify for the play off stage.
Midfielder Esteban Paredes scored four goals in 34 minutes as Santiago Morning came from 3-0 behind to beat Universidad de Concepcion 5-4.
Gabriel Vargas, Julio Cesar Laffatigue and Francisco Arrue put the visitors three goals ahead at halftime before Paredes scored in the 51st and 55th minutes to reduce the arrears.
Jaime Grondona equalised in the 61st minute and Paredes completed his hat-trick in the 76th minute to make it 4-3 only for Jose Luis Jimenez to equalise four minutes later. Paredes struck the winner in the 85th minute.
Audax Italiano twice came from behind to draw 2-2 with leaders Union Espanola despite having striker Fabiano Orellana sent off after 39 minutes.
Defending champions Colo Colo lost 2-1 at Rangers.
Cerro Porteno beat Guarani 2-0 to maintain their 100 percent record after three games of the Apertura championship while titleholders Libertad beat 12 de Octubre 2-1.
A torrential downpour forced the match between Racing Club and Penarol to be abandoned at the start of the second half. Leaders Defensor Sporting beat Bella Vista 3-0.