If there's one friendship that developed naturally in the Marvel Cinematic Universe, it's Steve Rogers and Natasha Romanoff. In the comics, the two have been close allies, but not necessarily friends. In the films, they develop a bond that is almost as close as the one Steve has with Bucky Barnes and Sam Wilson.

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Some fans have turned this into shipping the pair of heroes together, especially after their time together until Avengers: Infinity War. There's no direct evidence of a romantic relationship between the two.; however, there are a lot of scenes where they are friends.

10 Natasha Will Do the Things Steve Won't Do

Agent Sitwell Winter Soldier

In Captain America: Winter Soldier, Jasper Sitwell becomes a pretty obvious target for Steve and Natasha. In order to get information, they snatch him and take him to a rooftop. Sitwell calls Steve out on his threats because Captain America won't follow through on dropping him off the roof.

Natasha steps in and does the deed for Cap. Of course, Sam is nearby to catch him and bring him back for interrogation. Sitwell is convinced that if he's not cooperative, she will kill him, despite what Steve wants her to do. Natasha is tagging along on this mission to do the things Steve won't do.

9 When Steve Was On the Run, Natasha Was By His Side

Natasha has her reasons for helping Cap out in Winter Soldier. She was close to Nick Fury. It's also obvious that he was killed for information that she pulled off of the SHIELD ship at the beginning of the film. Their new friendship is established already and he is now hunted by SHIELD.

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She goes undercover with Steve and to throw off a nosy Apple Store Genius, she convincingly plays the role of his fiancee. Her assistance gets Steve the answers that he needs and gets him away from pursuing SHIELD agents. Without her assistance, Steve wasn't getting away without a massive fight.

8 Steve Tells Natasha To Get Her Feet Off Of The Dashboard

After eluding SHIELD Agents, Steve and Natasha "borrow" a car to go get answers at Camp Lehigh. The conversation goes to a few places, but Natasha does ask where Captain America learned to steal a car. Of course, it was in Nazi Germany.

Steve goes on to tell her that they're not stealing the car, they're borrowing it, and he then tells her to get her feet off the dashboard. She smiles instantly as she does. Natasha notices that Steve lives up to his reputation as a decent and good man.

7 Natasha Trying To Set Steve Up On A Date

At the beginning of Captain America: Winter Soldier, as they prepare to drop for the mission to rescue the SHIELD ship, Natasha is suggesting a woman he should date. Steve is brushing it off, but Natasha is persistent, even after landing on the ship.

This is the tell to the audience that Steve and Natasha's relationship has built into a friendship strong enough for her to suggest possible girlfriends for him. Of course, if Captain America wants to get a girlfriend, he can get one.

6 The Kiss On The Escalator

The first reason for the kiss in Winter Soldier is to get the pursuing SHIELD agents to look away from them. Natasha is a trained spy and can convincingly put on the role of an overly-affectionate couple. Steve is taken aback by it, but to his credit, he hangs in there.

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What's really interesting is that immediately afterward, Natasha takes a deep breath as she turns around. The look on her face is almost saying, "That was some kiss." Steve doesn't read too much into the kiss, but for just a second, he shook the spy.

5 Steve Physically Giving Support While They Are Talking To Her Ex

This is something very subtle. After failing to get Tony Stark to help them pull off a "time heist," Scott Lang, Steve, and Natasha go the next smartest person that they know. It just happens to be Natasha's ex, Bruce Banner, now a smart Hulk. Hulk comes off as a little annoying in his enjoyment of being the Hulk.

For Natasha, it must be a little uncomfortable, since this Bruce Banner is a little more imposing and almost obnoxious. It's very likely that there's a reason that she hasn't been using him on Avengers missions. Steve has his arm around her, physically offering support to her.

4 In Infinity War She Stays By His Side

In the years they have been on the run together, Steve and Natasha have developed a partnership. Whenever they are together, they are side by side. At the end of the film, as the weight of losing half of their friends kicks in, she runs to Cap's side.

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This also helps set the stage for Natasha to organize the Avengers in the next film. Natasha has grown and while her drastic change in appearance is part of being on the run, it also marks that she has grown significantly during this time.

3 Natasha Calls Steve Out On Lying To Her

In Captain America: Winter Soldier, Nick Fury gives Steve the zip drive that contains the secret files Natasha took from the ship. Before he is "killed" Nick Fury goes to Steve's apartment and that's where he's apparently murdered. After Nick is pronounced dead at the hospital, she asks Steve why Nick was there. Steve claims ignorance, and she tells him he's a terrible liar.

Natasha and Steve are friends. Natasha instantly recognizes that if Steve is hiding something from her, it must be serious. Instead of pressing the point around people that they may not be able to trust, she simply calls him out on it. She waits at the hospital for Steve to return from SHIELD headquarters and begins helping him.

2 "I Keep Telling Everyone That They Should Move On...But Not Us."

In Avengers Endgame, Steve comes to Natasha, who has taken over coordinating the Avengers. After she heads off his reflexive attempt to cheer her up, Steve sits down and walks her through his grief. His line, "I keep telling everyone that they should move on, grow, and some do, but not us," is a perfect thing for a friend to say.

Steve is telling Natasha that she's not alone in her feelings. They both feel like they should be doing something now that everyone is gone. This could be two friends talking over one death instead of billions. Their grief is consuming them and together, they almost come to the final stage, acceptance.

1 "I Didn't Want You To Be Alone"

Steve flies to London the second that he hears that Peggy Carter has died. After the funeral, Natasha comes up to him in an empty church and briefs him on which of their teammates has signed the Sokovia Accords. Steve, of course, won't sign them.

Then Steve asks Natasha why she came if she knew he would never sign the Accords. She simply tells him, "I didn't want you to be alone." Natasha is Steve's friend, and she knows that he's lost the last link he had to his past, and she just wants to be there for him. A true friend is one that will be there for you, even without being asked.

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