Mount Saint Joseph boys basketball trailed St. Frances by one with 10 seconds left in Sunday’s Baltimore Catholic League tournament semifinal.

After a timeout, there was no question who the No. 10 Gaels wanted to get the ball to — junior guard BJ Ranson. Boy, did he deliver.

Chauncey Word inbounded the ball from the baseline and found Brandon Holmes, who made a short pass to Ranson in the right corner. With Holmes nearby and two hassling defenders, Ranson faded and made a 3-pointer with just seconds remaining.

The junior combo had a game filled with big plays, none bigger than the last, to help the No. 10 Gaels to a thrilling 58-56 win over the No. 2 Panthers at Loyola University’s Reitz Arena.

Suddenly finding its top form in the past couple of days, Mount Saint Joseph — seeded sixth — upset No. 3 Spalding in a quarterfinal on Friday and then edged St. Frances on Sunday.

The Gaels (22-16) will take on No. 1 Mount Carmel in Monday’s championship game, set for 8 p.m. at Reitz Arena. The win was the 850th in coach Pat Clatchey’s 34-year career at the Irvington school.

Ranson, who finished with a game-high 24 points on 4 of 8 shooting from deep, said he was due.

“I knew it was in,” he said. “I was bound to make one. I missed one at Loyola and I turned one over [in the final seconds] at Mount Carmel. So it felt good to finally hit a game-winner.”

The final minute came with a close call made by the referees on the Panthers’ possession before Ranson’s heroics.

With St. Frances leading 56-55 and the shot clock winding down, Kamauri Lawson drove the baseline and fed Jaylen Allen inside. He was fouled and finished at the rim as the shot clock buzzer went off. After the referees consulted, they ruled the shot came after the shot clock expired with 10.6 seconds left to play.

St. Frances coach Nick Myles declined to comment after the game.

Ranson then turned hero for the Gaels.

“He was balling today, playing with great confidence. That was a huge shot. He’s built for that,” Clatchey said.

In the area’s fiercest rivalry in recent years, the Panthers won both regular-season meetings and then claimed a comfortable 72-52 win over the Gaels in last week’s Maryland Interscholastic Athletic Association A Conference playoffs.

But building off Friday’s 66-65 win over Spalding, the Gaels stayed close throughout on Sunday. They enjoyed the biggest lead of the game at 43-37 midway through the third quarter and then hit the clutch basket at the end to advance. On Monday, they’ll take aim at the program’s 10th BCL tournament crown.

“We’re just trying to get better one game at a time. We haven’t had the best season, but now is the time to play your best ball and our guys are believing in what we’re doing,” Clatchey said.

Holmes finished with 11 points, three rebounds, three blocked shots and two steals. The Panthers got a 20-point, nine-rebound performance from Trent Egbiremolen with Trence Jones adding 11 points.

Mount Carmel won both regular season games against Mount Saint Joseph — 53-51 on Dec. 11 and 47-37 on Jan. 22. Do the Gaels have one more upset win left this season? Ranson thinks so.

“We’re all just locked in together now. We’re a younger team, but we’ve gotten older as the season went on and now we’re mature and ready to blossom. We just got to play hard — play like we did today,” he said.

MSJ — 14-20-12-12 — 58

SFA — 18-17-11-10 — 56

MSJ: Ranson 24, Green 7, Holmes 11, Word 4, Early 7, Purnell 5

SFA: Cannady 4, Jones III 11, Egbiremolen 20, Fleming 9, Lawson 9, Allen 3

Mount Carmel advances: No. 1 Mount Carmel held on to beat John Carroll, 45-41, in the other semifinal.

The Cougars, who won the MIAA A Conference championship last week, will take a 33-4 record into Monday’s title game. Mount Carmel coach Tony Martin will have a chance to become the first coach in BCL history to win titles for three teams. He previously won tournament titles for Spalding (1999) and John Carroll (2010-11 and 2015-16).

The Cougars’ 15-point second-quarter advantage was whittled down to one possession late in the third before they made five straight stops and added to their lead. Baskets from Gage Howard, Mario Tatum and two straight by Samartine Hill provided a 43-38 advantage with 1:42 to play.

A 3-pointer from John Carroll’s Caden Chinnia-Fallline made it 44-41 with 12 seconds left, but Hill made one of two free throws three seconds later to secure the victory.

The Cougars have found ways to win close games all year and their latest gives them a chance to sweep the MIAA A and BCL crowns.

“We reminded them in the huddle that we’ve won every close game we’ve played this season and that score was indicative. It’s an offensive era, but, at the end of the day, defense wins this time of year in every sport,” Martin said. “We were a little better than them when it counted.”

Tatum finished with 12 points to lead the balanced attack, scoring seven in the first quarter to get the Cougars off to a good start. Wilson scored seven of his nine points in the second to help Mount Carmel build its biggest lead at 26-11 midway through the frame.

John Carroll forward Andrew Clark helped bring the Patriots back with a game-high 18 points and eight rebounds.

Two free throws from Parris Lee cut the deficit to 35-34, but the Cougars responded with baskets from Howard and Tatum on their next two possessions to expand their lead to five.

“It’s high-level basketball and we weren’t ourselves in the first half. But we found ourselves and put [ourselves] in position to have success and win the game, and we came up short,” John Carroll coach Seth Goldberg said. “I’m super proud of my guys. They were incredible in the second half and gave us a shot to win it.”

The Patriots finished the season with an 18-14 record.

JC — 5-15-12-9 — 41

MC — 13-15-6-11 — 45

JC: Abel 9, Chinnia-Falline 9, Lee 5, Clark 18

MC: Howard 7, Wilson 9, Scott 4, Mancho 2, Rudusans 2, Tatum 12, Hill 9

Have a news tip? Contact Glenn Graham at ggraham@baltsun.com, 410-332-6636 and x.com/GlennGrahamSun.