China Wrap: Vagner Love hat-trick inspires Luneng
The Brazilian boasts four goals in the AFC Champions League this season and took his Chinese Super League tally to five during a fine performance at the Workers' Stadium.
Guoan had only lost once in the league heading into the encounter, yet the hosts were on the back foot as early as the ninth minute as the former CSKA Moscow man opened the scoring.
The home side's cause was hindered by a straight red card for Joffre Guerron in the 18th minute and Luneng duly took advantage as Vagner Love added a further two goals in the second half.
Lungeng leapfrog Guoan into second, with the win representing ideal preparation for a make-or-break Champions League group-stage encounter with Cerezo Osaka in midweek.
Guoan must quickly bounce back ahead of a crucial contest of their own in the continental competition against Seoul.
Reigning champions Guangzhou Evergrande also face a vital Champions League encounter with Yokohama F Marinos, and showed no signs of complacency before that fixture in a 2-1 triumph over Shanghai Shenhua at Tianhe Stadium.
Goals either side of half-time from Feng Junyan and Gao Lin gave Marcello Lippi's men a two-goal lead and - though Firas Al Khatib grabbed a late consolation from the penalty spot - Evergrande saw out the win and retained top spot.
Shanghai SIPG were held to a 1-1 draw at lowly Dalian Aerbin, meaning Guangzhou R&F moved to fourth as they overturned a 2-0 deficit to triumph 3-2 at strugglers Changchun Yatai, with Davi proving the hero thanks to a 93rd-minute winner.
Elsewhere on Sunday, rock-bottom Harbin Yiteng remained pointless after surrendering a lead in a 2-1 setback at Hangzhou, while Liaoning Whowin's early-season woes continued in a 2-0 defeat at home to Tianjin Teda.
Shanghai Shenxin and Jiangsu Sainty played out a 1-1 draw, while Henan Jianye were defeated 2-1 by Guizhou Renhe on Friday.