Genia received two yellow-cards in nine minutes for professional fouls as his Hanazono Kintetsu Liners suffered a heavy 50-12 loss to Shizuoka Blue Revs on Saturday.
The 36-year-old's dismissal, which came 14 minutes into the second half, didn't have a major impact on the outcome as winless Kintetsu trailed 36-12 at the time against a Blue Revs side who have lost their skipper, Springbok loose forward Kwagga Smith, for the season after he sustained an adductor tendon injury.
Smith is one of three South Africans currently on the injured list in Japan, with halfback Faf de Klerk and centre Jesse Kriel also out long term.
De Klerk and Kriel's Yokohama Canon Eagles were shot down by Kobelco Kobe Eagles, losing 31-27 as ex-Chiefs five-eighth Bryn Gatland scored 21 points for the winners.
The win snapped a three-game losing streak for former Wallabies coach Dave Rennie's side, lifting them to seventh on the table.
Kobe are one place below Kubota Spears Funabashi Tokyo Bay after the defending champions prevailed 18-17 in a thrilling finish against a Ricoh Black Rams Tokyo outfit coached by Aussie Peter Hewat.
The Black Rams looked to have won the game when a penalty try in the last minute gave them a two-point lead, but the game continued.
This allowed Kubota to steal it when South African-born Gerhard van den Heever, who was deputising for injured Wallaby Bernard Foley, kicked the winning penalty goal.
All Blacks loose forward Shannon Frizell scored his sixth try, and is the competitions joint leading try-scorer, as Toshiba Brave Lupus Tokyo retained their unbeaten record by beating Toyota Verblitz 28-12.
The anticipated clash between rival All Blacks No.10s lasted only 16 minutes before Beauden Barrett left the field, leaving countryman Richie Mo'unga to steer Brave Lupus to victory.
Former Wallabies coach Robbie Deans' Saitama Panasonic Wild Knights are top of the championship table, with Brave Lupus two points behind.
The league now pauses for two weeks to cater for Cross Border rugby, where the Super Rugby Pacific's Blues will play Tokyo Suntory Sungoliath and Yokohama Canon Eagles, while the Chiefs will face Saitama Panasonic Wild Knights and Kubota Spears Funabashi Tokyo Bay.
