The last CSL victory for Shenhua came in the middle of August with a 1-0 win over Jiangsu Suning, followed by two defeats and five draws.
The striker said that joining Atletico Madrid was an "attractive challenge" and that he had spoken to Antoine Griezmann and Uruguay international Diego Godin about the club.
In the Changzhou division, Kunshan FC edged Changchun Yatai 1-0, Nantong Zhiyun held a 1-1 draw with Sichuan Jiuniu, and Xinjiang Tianshan Leopard tied with Heilongjiang Lava Spring 0-0. Enditem
Huanghai got the opener in the 37th minute when Gao Xiang headed in left-back Yang Yu's cross.
The top four teams at the end of the qualifying tournament will automatically earn a World Cup berth. The fifth-ranked side will advance to an intercontinental playoff over two legs.
Speaking ahead of his side's Carabao Cup game against Barnsley on Wednesday, Chelsea coach Frank Lampard said that former Chelsea goalkeeper Petr Cech, who is now a technical and performance advisor at the club, had been instrumental in the signing.
After the restart, Esteghlal were quick to cement their place in the Round of 16 with a third goal, as Karimi supplied a chipped cross from the edge of the penalty area for Cheick Diabate, who guided his header past Al Owais to make it 3-0.
The 24-year-old striker has put to pen to paper on a five-year deal which binds him to the "Bulls" until June 2025.
The league debut comes after another difficult week, which followed a complicated summer in the wake of Barca's 8-2 thrashing to Bayern Munich in the Champions League. That defeat saw Quique Setien sacked as coach and replaced by Koeman and led to a clear out of the dressing room, which has so far seen Ivan Rakitic, Arturo Vidal, Arthur Melo, Nelson Semedo and Luis Suarez all leave the club.
"You know what is happening in life and in football and what the press are saying. My departure had been talked about and the coach's phone call confirmed it," explained Suarez.
"I am very happy to represent Shenhua. I think it is a tough game and our opponents are very strong, but even one point is important to us," said Martinez after the game. Enditem