We are just a day away from "Grey's Anatomy" season 10 episode 21 which will also be cast member Sandra Oh's character, Cristina Yang's last appearance on the ABC hit series.

According to E! News, fans should brace themselves for a difficult Thursday night as Cristina will be forced to make her most difficult decision ever.

Fortunately although we still have to wait for her final episode we did find a sneak peek with some spoilers.

In the promo clip of the episode titled "Change of Heart," Cristina is forced to make a potentially fatal decision for a family.

Fans of the show were initially shocked back in August when Oh announced she would be leaving the series after 10 seasons.

The actress said, "It's been a great privilege to play the character of Cristina Yang on GA and I am both sad and excited to see where this, her final season will take her."

The creative mind behind the series, Shonda Rhimes promised fans that they will indeed be satisfied with the way Cristina's storyline ends.

She explained, "When Sandra walks out of my door, 'Grey's Anatomy' will be once again be forever changed."

As we are forced to say goodbye to Cristina we will also see the return Isaiah Washington, whose character Dr. Preston Burke left Cristina at the altar in season three.

Rhimes revealed, "He gives her story that full-circle moment we need to properly say goodbye to our beloved Cristina Yang."

 "Grey's Anatomy" airs Thursdays at 9 p.m. on ABC.

To check out the sneak peek clip click HERE.