One of the most anticipated moments at the 2021 Oscars was the Best Actor award, in part because it was assumed that it would double as a tribute to the late Chadwick Boseman, The actor died last summer at the age of 43, and was widely tipped to win Best Actor posthumously for his performance in "Ma Rainey's Black Bottom." He had already picked up both the Golden Globe and the SAG this year.Boseman was the final person to appear in this year's In Memoriam segment, which seemed to confirm everyone's expectation that he would take the prize. But instead, when the moment came, it was Anthony Hopkins who won for his performance in "The Father" – and the actor wasn't in attendance. It was an anticlimactic ending to the show to say the least, and Twitter was immediately flooded with reactions from confused and upset viewers. Many commented on the unusual order of awards at this year's ceremony – and whether the rejigging had anything to do with the presumptive Boseman win. Usually, Best Picture is the final award of the night, but this year the producers saved Best Actress and Best Actor for last. Many were speculating that this was because they expected (just like all of us) that Boseman was a shoo-in, and so structured the ceremony to end on a moving tribute to the late actor.A quick note here: the producers don't know in advance who will win. That information is known solely to the good people at PricewaterhouseCoopers, the accounting firm who handles the results. So although it's not confirmed, it's entirely possible that this entire ceremony really was designed to build up to a presumptive result that didn't happen. Which explains why that ending landed like such a lead balloon.Though Hopkins' performance in "The Father" has been widely acclaimed, there was a feeling of intense anticlimax when his win was announced, as a quick glance at Twitter will attest. But film executive Franklin Leonard had perhaps the most resonant and constructive reaction.Hopkins was also surprised by his historic Oscar win. The 83-year-old thespian became the oldest winner in the acting category for his performance."Good morning," Hopkins said in a video posted to Instagram. "Here I am in my homeland in Wales and at 83-years-of-age I did not expect to get this award. I really didn't."Hopkins expressed his gratitude to the Academy and to Boseman. "I want to pay tribute to Chadwick Boseman who was taken from us far too early," Hopkins said."I really did not expect this, so I feel very privileged and honored," the actor added. "Thank you."CNN contributed to this report.