Returning to action for the first time since June, undefeated Canadian star Sarah Kaufman will face her toughest test to date at Strikeforce Challengers 5 on November 20th when she takes on Japanese standout Takayo Hashi, who has tasted defeat just once in her career.

Kaufman will be looking to position herself in line for a title fight in the near future, while Hashi, one of the top female fighters in Japan today who holds big victories over Amanda Buckner and Hitomi Akano, will aim to make an immediate impact in her Strikeforce debut.

The fight will be part of the televised main card and could serve as a co-main event. It was thought that Kaufman’s next fight would be for a newly-created Strikeforce Women’s 135-Pound Championship, but it now appears as though she will have to get past Hashi first.

Kaufman (10-0-0) won her first eight fights by a form of knockout and captured the Hardcore Championship Fighting Women’s Bantamweight Championship in the process. She has since gone on to defeat skilled wrestler Miesha Tate and submission ace Shayna Baszler inside the Strikeforce cage.

Though her fights with Tate and Baszler went the distance, Kaufman has retained her exciting style and striking dominance since joining the Strikeforce ranks and a victory over Hashi would put Kaufman just outside of the top five female fighters in the world.

Hashi (12-1-0) suffered her only defeat in a submission loss to fellow Japanese contender Hitomi Akano at SmackGIRL: “Dynamic!!” in August of 2005. She has won eight straight fights and avenged the loss to Akano by winning a Unanimous Decision in their 2007 rematch.

Hashi also holds a win over highly-ranked Amanda Buckner and is coming off of a submission of Chisa Yonezawa at Valkyrie 2 in April. Should Hashi become the first woman to defeat Kaufman, she would instantly vault to the top of the Strikeforce women’s 135-pound division.

The winner of the fight must surely compete for a title in their next fight, though the only potential challenger to face the winner would be Roxanne Modafferi, who had previously hoped to battle Kaufman this year.

Modafferi is once again left out of a fight that she arguably deserves to be a part of, but Strikeforce could bring her in to face the winner of the Kaufman/Hashi fight to determine the promotion’s first women’s 135-pound champion.

Elsewhere on the November 20th card, a second female fight will air on the main card when Kerry Vera (wife of UFC contender Brandon Vera) battles Kim Couture (ex-wife of multi-time UFC champion Randy Couture) in a 135-pound bout.

The fight between Kerry (1-0-0) and Kim (1-1-0) will air less than one week after UFC 105, which is headlined by a light heavyweight fight between their male counterparts, Brandon and Randy.

Headlining Strikeforce Challengers 5 is a welterweight showdown between fast-rising star Tyron “T-Wood” Woodley (4-0-0) and Rudy Bears (10-3-0).

Rafael “Feijao” Cavalcante will meet Aaron Rosa at 205.

The event will air live on Showtime in the U.S. and Super Channel in Canada.