Robert Ryan did not receive an Oscar nomination for portraying Deke Thornton in The Wild Bunch.
When the massacre of a shootout occurs Ryan is excellent in the one moments where Thornton clearly has a good shot on Pike but hesitates to take it. Ryan's reaction is perfection as you see in his eyes an understanding towards Pike and he effectively gives a window into his past with Pike. The reason they have a past though is because Thornton was a former member of the bunch before he was captured mainly due to Pike's own carelessness. Ryan does not show ill will towards Pike being the cause of going along with a railroad man's attempt to take down the gang. This rather comes from his desire never again to return to prison where in a quick flashback we see he was flogged. Ryan is very good in the brief moment where Thornton expresses this desire as in the words he realizes the obvious pain and horrible treatment he received in prison. Although we only see one thing he suffered from in the prison Ryan manages to suggest far more. Ryan does well in the moment as he honestly makes Thornton particularly sympathetic, and honestly his motivation is technically far more noble than the bunch who really just want money.
Ryan's very good in portraying Thornton though as essentially the only competent person who is on the trail of the bunch since the men he has to work with seem a bit too focused on their prize. Ryan's does well to express the exasperation in Thornton whether it's directly to the railroad man, or just in his silent distaste in the men's attitude. Ryan again elicits the right sort of sympathy as his passionate hate reflects just how uncouth and incompetent the posse he is given are, but as well exudes that frustration of a man forced to do something he has no desire to do. What Ryan also does particularly well though is create the competence in Thornton with his performance. Thornton constantly saying the men with him essentially are scum, sometimes right in their general vicinity, could make just seem like the foolish villain himself. Ryan though creates the intelligence in Thornton particularly well in the scenes where he attempts to stop the bunch. Ryan's short moments before the start or during the action are superb as he shows Ryan makes it so Thornton's superiority over his men is a well earned given.
The best part of Ryan's performance though is the way he keeps Thornton's relationship with the bunch as a constant even though there is only a single scene where he directly speaks with a member, and past that even the only flashback is only a very short one where he barely interacts with Pike. Ryan though effortlessly finds the connection between Thornton and the men in every instance. When he sees them succeed and ride off in any instance Ryan is excellent in exuding that nostalgia in the men. What I find the most interesting though is that Ryan does not exactly play it as though Thornton wants to be doing exactly what they're doing per se. Rather what Ryan seems to realize though is a longing to be free in Thornton above else, and to be able to be the man he once was. A great moment of his performance is at the end of the film after the bunch takes on about a hundred men too many. Ryan does play the scene as an overt sadness in Thornton but is very moving by playing it as though Thornton accepting that they finally faced the inevitable on their own terms. This is very strong work from the underrated Ryan and his final reaction is a great sendoff essentially for the bunch as he seems to exhibit one last reminder of the camaraderie they once had.