Gamba have 12 points from four second-stage games though free-scoring Urawa Reds can reclaim top spot with victory at Oita Trinita on Sunday.
Oguro struck in the 11th and 34th minutes against bottom club Kashiwa twice scoring from close range to take his tally for the season to 14.
JEF United Ichihara went second after a 2-1 home win over Tokyo Verdy despite playing the last 33 minutes with 10 men.
Champions Yokohama F-Marinos swept aside struggling Jubilo Iwata 3-0 in Tokyo to take top spot for just a couple of hours.
Daisuke Oku and Japan Under-23 striker Daisuke Sakata gave Yokohama the initiative with first-half goals at National Stadium.
South Korea striker Ahn Jung-hwan sealed the points with a close-range header in the 62nd minute after good work from Oku.
Yokohama improved to nine points from four second-stage matches to stay in the hunt for a fourth successive stage title.
Four-times champions Kashima Antlers battled back from two goals down to beat Cerezo Osaka 4-3 at home for their second win of the second stage.
Elsewhere Brazilian striker Kelly converted two first-half penalties to help FC Tokyo to a 3-1 home win over 10-man Vissel Kobe.
Shimizu S-Pulse comfortably beat Sanfrecce Hiroshima 3-0 in Shizuoka.