Relationships are foundational to the long-running medical drama Grey's Anatomy. Human drama steeped in a wide gamut of emotions generated from love, joy, pain, loss, and death, are crucial to the many storylines the series has given fans over the years. But while romantic arcs are, of course, fan favorites, the series is also replete with friendships between individuals - some expected and some that fans never imagined would happen.

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However, even those unlikely friendships were often well-received and some of them seemed to make perfect sense once the fans got on board with them. In fact, a few of those unexpected friendships, like the ones between Miranda and Derek, April and Arizona and Arizona and Richard, turned out to be more meaningful than many of the more expected friendships.

Arizona & April

Arizona and April talking on Grey's Anatomy

These two developed a lovely friendship quite out of the blue, but once it happened, fans got on board with it pretty fast. Both April Kepner and Arizona Robbins were beloved characters who had been through devastating ups and downs in their own lives, so it was good to see them find some comfort in each other.

For instance, Arizona was a pillar of support for April when she and Jackson separated and was one of the few people who knew about April and Matthew getting back together. April was also seen to be a supportive friend, comforting Arizona when she discovered the couple had broken up or when she was missing Sofia.

Owen & April

April and Owen side by side in Grey's Anatomy

Owen Hunt was the rugged ex-military trauma surgeon while April was the epitome of the shy resident with a nervous temperament. The two couldn't have been further apart and it seemed unlikely that they could ever be friends.

However, they did develop a friendly dynamic, with Owen mentoring April into becoming an exceptional trauma surgeon herself. April was even asked to be Owen's best man at his second wedding to Amelia Shepherd and Owen was there for her when she almost lost it before the board exams.

Jo & Jackson

Jo Wilson with Jackson in Greys

Another unlikely friendship that emerged in the seventeenth season was between Jo Wilson and Jackson Avery. Given how things ended for Jo with Alex, she was left at a loose end and Jackson, of course, never quite found the right person after he broke up with April.

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The two thus ended up sleeping together casually and developing a sweet friendship where they could unburden themselves to each other. Of course, like most of Jo's relationships, this one didn't last too long, but it wasn't bad while it lasted, albeit being unexpected.

Callie & Derek

Callie sitting with Derek in conference room

Callie wasn't shown to be close to Derek until after Mark Sloan died in the horrific plane crash of season 8. Callie and Derek were the only people Mark had been truly close to and so it made sense that these two should somehow come together in their grief, although fans never really anticipated it.

Callie developed a camaraderie with Derek while operating on his million-dollar hand. They then started working together on other projects until Derek eventually agreed to join the panel of experts put together for brain mapping by the White House.

Arizona & Teddy

Robbins and Altman talking in friendly manner

Arizona also had another friendship that fans didn't really see coming and that was with Teddy. Teddy was at the time just coming to the realization that Owen had chosen Cristina over him. She seemed to be in need of support and of a friendly face, and Arizona, given her temperament, was happy to offer her a shoulder to lean on.

Teddy and Arizona's friendship didn't last too long as Teddy moved to Germany. But the latter did try to help her snap out of her feelings for Owen by dating Mark casually, and fans would have liked to see more of them, perhaps even as more than just friends.

Miranda & Derek

Derek breaking down and Bailey stopping the elevator

Another friendship that fans never really anticipated was the one between Miranda Bailey and Derek Shepherd. Miranda never minced words when it came to Derek and the latter seemed to actually appreciate her fearlessness.

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Gradually, a beautiful friendship arose between the neuro attending and the surgical resident. Two of the most heartwarming scenes in the series happened between these two inside the infamous elevator. Once, Miranda stopped the elevator to give Derek a minute to get himself together after his patient died tragically and the same courtesy was extended to Miranda by Derek when she herself needed a moment while coping with George's death and Izzie's illness.

Arizona & Nicole

Arizona lying on the grass with Herman

Arizona Robbins's friendships were all a tad unexpected. Not only were fans taken aback by what turned out to be a great friendship bordering on sisterhood between her and April, but Arizona's friendship with the surly Nicole Herman was also quite astonishing, albeit heartwarming.

Nicole's nature was almost diametrically opposite to Arizona's sunny personality. Yet, the two began to respect one another and in time developed a connection that would make even the toughest fans teary-eyed. It made sense that it was Nicole who offered Arizona that final incentive she needed to move to NY for her daughter Sophia.

April & Nathan

April not only had an unexpected friendship with Owen, but she also had a very beautiful relationship with the handsome Nathan Riggs. Nathan had worked with her in Jordan when the latter had gone off to find her way after the tragic death of her son Samuel. When viewers first saw Nathan, they were surprised to find him on such friendly terms with April, and some even wondered if there might be anything more to it.

It was a good choice on the writers' part to not show anything other than friendly affection between the two. If there is anything that Grey's can pride itself on, it is the variety of human relationships that it has shown so very naturally, instead of leaning towards the stereotypical.

Richard & Arizona

Arizona and Richard talking in Grey's Anatomy

Beautiful friendships can emerge even when least expected. Richard's friendship with Miranda was beloved despite being fraught with tension, but, over time, he developed a lovely relationship with Arizona. The two supported each other as they both grappled their way through loneliness.

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Richard was there for Arizona throughout her custody battle with Callie over Sophia. In fact, he was literally the only colleague who supported Arizona wholeheartedly, until Miranda testified in her favor quite spontaneously. Richard and Arizona made unlikely friends but their friendship gave fans some heartwarming moments.

Cristina & Dr. Thomas

Cristina standing beside Thomas in Grey's Anatomy

One of the most unexpected friendships that literally no-one imagined would ever happen emerged between the elderly Dr. Thomas and Cristina Yang. Thomas had been one of the examiners who took Cristina's orals and the latter, it seemed, had well and truly managed to wind him up the wrong way.

However, once Cristina landed up in Mayo Clinic after the plane crash, she found herself working with Dr. Thomas who took her under his wing and gradually started mentoring her. The latter, true to her nature, was critical of him at every step, and the two acknowledged their generation gap.

But in time, Cristina came to appreciate Thomas' old school techniques and he became her only friend. His sudden death hurt Cristina more than she would ever admit. Their friendship, while unanticipated, was one of the most beautiful relationships Cristina had that was separate from her equation with Meredith.

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