The second set wasn't much different, as Raonic continued to outplay del Potro. The difference was that del Potro avoided making the costly error that would result in a Raonic break. That allowed the two players to head to a tiebreaker, where the pressure seemed to finally get to Raonic.
The Canadian, who had been playing flawless tennis early on, started to get a little tight in the tiebreaker. He stopped being aggressive and his nerves opened the door for del Potro to get himself back in the match.
With the crowd cheering him on, del Potro took control of the tiebreaker with his serve. Raonic, meanwhile, was struggling with his, which allowed the Argentine to force a third set without breaking much of a sweat.
In between the second and third sets, Raonic went into the locker room for a quick break. At the time, it appeared that del Potro was thrown off by the delay. With del Potro looking somewhat rattled, Raonic took advantage with a break.
But it actually might not have been Raonic's trip to the back that threw del Potro off, as the third set started off with four straight breaks. From there, however, the two held all the way to the deciding tiebreaker.
At this point in the match, the atmosphere in the building really started to swing things. The Miamifans were giving del Potro all the love that they possibly could, and the Argentine was clearly feeding off of it. It took two hours and 52 minutes, and three sets that nearly went the distance, but his long, successful night was finally over.
Looking back, it's hard not to imagine Raonic beating himself up the rest of the week. Del Potro was clearly off his game, and he gave the Canadian every opportunity to steal this victory. And despite Raonic playing some of his best tennis since 2016, he was unable to win the points that mattered the most.
Del Potro, meanwhile, continues to find ways to win. The world No. 6 was seemingly dealing with an injured back in this match, which caused him to ask a trainer for pain relievers towards the end of the first set. It's impossible to predict how he'll be feeling in his semifinal matchup with John Isner, but he should benefit from having a day off to rest.
The 29-year-old will also have the satisfaction of knowing that he is 6-3 in his career against Isner. He'll just have to be ready to handle the American's serve, which has not been easy for anybody thus far.
