A few hours later word had spread throughout the baseball world that Kalas was dead at 73.
"It's shocking to me that it's already two years later and we are back in Washington," centerfielder Shane Victorino said. "You don't want to think about sad moments, but [this anniversary] kind of hits home again. Two years to the day? Wow."
Victorino led two salutes that April afternoon. The first one came in the dugout before the game when he and Jayson Werth lit cigarettes in tribute to Kalas, a chain smoker who genuinely loved the habit. The second came when Victorino hit a home run and saluted the press box after he crossed home plate.
"It definitely hit me that I would never hear that voice again," Victorino said.
Tom McCarthy was probably the man most impacted by Kalas' death because starting with that afternoon game, he became the team's lead play-by-play man on television, a role that had belonged to Kalas for as long as most Phillies fans could remember.
"It was the hardest day I've ever had," McCarthy said. "We wanted to make sure we paid proper tribute to him. I couldn't have done it without Sarge [Gary Matthews] and Wheels [Chris Wheeler], but also without Jeff Halikman, our producer, and Ray Tipton, our director. They were unbelievable. That game became a tribute and it was really impressive, the stuff they put together."
Tipton had worked with Kalas since 1983 and this was the second time in his career that he felt a profound sense of loss and had to work through it. The previous time was in 1997 when Richie Ashburn died suddenly during a road trip in New York.
"Once we realized it was out of our hands, you realized you had to do a broadcast in about an hour and 40 minutes," Tipton said. "We tried to collect our thoughts and determine a game plan on how to treat a very tragic and delicate situation. I had been through it with Richie.
"Richie's might have been tougher now that I think about it. Even though we had more time, Richie's was just so, 'How could this be?' We knew Harry was struggling. He kept it to himself, but we could see it. Richie's might have been more difficult, but they were both difficult."
McCarthy has had the difficult task of following Kalas, and he knows better than to say he has replaced the Hall of Fame broadcaster.
"You'll never replace him," McCarthy said. "You just succeed him. Somebody has to always succeed the player, the broadcaster, the president, so you just try to be yourself. Harry told me that. You have to be yourself, and Wheels has always told me that, too."
McCarthy said his predominant thought after hearing that Kalas had been taken to the hospital was that he'd soon be returning.
"I kept hoping he'd come back," McCarthy said. "You know once he went to the hospital he would come back an hour later and he'd be fine and be able to call the game and move on from there."
Wheeler saw Kalas being taken out on the gurney and was not surprised when he heard his longtime broadcaster partner had died.
"It didn't look good," Wheeler said. "I didn't see him breathing and he was white. That was the hardest game I ever did. Tom did a great job. The hardest part was sitting there getting your thoughts together knowing that we were going to be on in an hour and a half after we heard this. Everybody told us that what we did that day helped them get through the day."
McCarthy said he remembered a tear running down Matthews' face during the opening of the telecast. Matthews said he believes he was more embraced by the fans as a broadcaster after that telecast.
"After that, I kind of stopped getting roasted," Matthews said. "Obviously, that was a real sad day and every time you come back here it's a real sad day realizing that you lost a friend. And Harry helped me out so much."
Whenever something special happens, McCarthy said his thoughts always turn to Kalas.
"We all wish he was here," McCarthy said. "I wished he was here when they were in the postseason in 2009 and I wished he was here when Roy Halladay threw the perfect game because I'd love to hear how he would call it.
"I still think that nobody made the big call better than he did, so I always think about some of the great memories since then and what he would have said and how he would have said it."
Contact staff writer Bob Brookover at email@example.com. Follow him on Twitter at twitter.com/brookob.