Poca's Cameron Cottrill (12 points) shaved the deficit back to 36-35 on a leaning three-point play with 32 seconds to go before Casto answered with his two foul shots to bump the lead back to three.
Matt Chandler took a feed from Hayden Bailey and made a layup for the Dots with 7.4 seconds left and they called a timeout, down 38-37. George was fouled and missed the front end of a 1-and-1, giving Poca one final chance.
The Dots got the ball to Adam Sigman, who brought it down the right side of the floor as time dwindled. He waited for a teammate to come open, but found none, and missed a 15-footer at the buzzer.
"When Garret went out,'' said Irish coach Bill McClanahan, "I was really pleased with the way that David Godwin and Nick and Keifer [Hovorka] and Zach stepped up and took care of the ball and handled the ball and handled Poca's pressure. Because Poca had fouls to give and they were gonna come at you hard anyway, and with fouls to give meant they could come at you twice as hard.
"I thought we wouldn't have made those same decisions a month ago with that same group on the floor. So that's a positive to take with us getting ready for the tournament. It's a good growing process for the guys who stayed on the floor, and it also lets Garret know he can trust his teammates. He has a huge role on this basketball team, but he's got guys he can trust and play with.''
McCarty added 10 points for the Irish, who led 23-20 in rebounding. Hovorka led the team with three steals - each leading to a transition basket at the other end.
Noah Frampton headed Poca's offense with 14 points and grabbed a team-high seven rebounds. Chandler added nine points and six boards.
Dots coach Allen Osborne doesn't think his team's recent losing spell will curb momentum heading into sectional play.
"We're four possessions from winning those four games,'' Osborne said. "It's just how you handle it. We're not going to let that put us down. We're going to try and get better and learn from those things.
"We had a chance at the buzzer tonight. We did a lot of right things. We fouled the right people, put them on the 1-and-1 and had a chance to win. That's all you can ask for.''
Reach Rick Ryan at 304-348-5175 or rickr...@wvgazette.com.