The Australian grand slam winner endured a dry spell in 2014, with her run at New Haven in August representing her first back-to-back wins at any tournament since the French Open.
However, under the tutelage of Nick Kyrgios' former coach Simon Rea, Stosur went on a deep run at the ongoing China Open in Beijing.
It was a much-needed string of results for the Australian number one, who has a large slab of rankings points to defend after her strong finish to the 2013 season.
Stosur - a two-time Japan Open champion - is joined by five other top-40 players in the main draw, namely American Madison Keys (32), Ukraine's Elina Svitolina (33), home favourite Kurumi Nara (37), American Coco Vandeweghe (38) and Kazakh Zarina Diyas (39).
Great Britain's Heather Watson - ranked 47th - won the title in Osaka in 2012, her only appearance in a WTA Tour final in her young career, and comes to the event in need of a match win.
Watson has five straight first-round losses to her name.
Other winners of the five-year old tournament are the retired Marion Bartoli and Thai veteran Tamarine Tanasugarn.
Misaki Doi and Misa Eguchi join Nara as other local hopes at the WTA International hard-court event, which has a prize money pool of $250,000.