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Credit: Howard Wise/JPI

CBS soap vet flashes back to time spent with a Daytime Emmy Award-winning legend and a dear friend.

Longtime fans of The Young and the Restless will forever remember the love/hate relationship between Katherine Chancellor and Jill Abbott — and Jess Walton took to Instagram to pay tribute to the daytime rivalry and her “favorite acting partner ever,” not to mention “a friend like no other.”

Among the posts and photos was this throwback of Katherine and Jill — and you know what they say about keeping your enemies close…

As well as this one of the actresses from years gone by…

However, the one that caught our eye, and brought back so many memories of their rivalry over the years, was another pic of Katherine and Jill that Walton captioned, “What do you think we were thinking?”

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The way Katherine was looking at Jill… she not only had her eye on her but likely was already two steps ahead in regards to what Jill might have been thinking — or planning.

Fans had some fun responses to the daytime vet’s question, including Michael Kenney, who replied, “Phillip loved me more,” as well as Michele Strode, who suggested that Jill had her eye on another man and wondered “how much he’s worth,” as Kay was thinking, “Oh God, Jill’s at it again.” And Patricia Perrotto added, “Don’t even think about going after that man, Jill.”

The CBS soap had a cute comeback and figured one or both of them were “wondering where Esther [was].”

Join us as we look back at the life and loves of Katherine Chancellor in our gallery below, which includes one of the explosive moments when she and Jill came to blows.