The mother of Mitch MacLean — a ballplayer from P.E.I. who was killed in an Alberta murder-suicide last week — read her poem called Last Time at the Plate during her son's funeral, which was attended by an estimated 600.

Cars were lined up along the road by Winsloe United Church, just north of Charlottetown, for the service. An overflow room was set up for those who could not get one of the 220 seats in the chapel.

A former girlfriend of MacLean's, Melia Thompson, said after the service it was "exactly what Mitch would've wanted."

MacLean was a promising young baseball player, and the sport played a prominent part in the service.

The poem read by his mother was one she had written herself. His casket left the church to the tune of Centerfield by John Fogerty.

Mitch MacLean was a promising young baseball player, and the sport played a prominent part in the funeral service. (Facebook memorial page)

Kevin Kvame, the general manager of MacLean's baseball team in Alberta, and several of his teammates flew across the country for the service.

Kvame told CBC News on Thursday morning that the group from Alberta had already met with the MacLean and Craswell families.

"The families are liking to hear the stories. We bring some stories from out West that they don't get to hear every day, and we're getting to hear stories from out here," said Kvame.

"It's been a very comforting exchange of information."

Kvame said MacLean and Craswell were always a pleasure to be around.

"These guys were just fun loving, you know, life-of-the-party type of individuals that just captured a room when they were in it," he said.

"They just captured their teammates, their friends, other college students. They were just incredible young people."

Shooter was stalking ex-girlfriend

MacLean, 20, was shot to death by Derek Jensen, who also killed his ex-girlfriend, 21-year-old Tabitha Stepple, and Tanner Craswell, 22, from P.E.I., before killing himself.

Shayna Conway, a 21-year-old from P.E.I., was the lone survivor of the shooting, which has rocked communities both in Alberta and P.E.I.

Investigators have determined Jensen was searching for Stepple early Thursday along Highway 2 when he spotted her SUV stopped at a 7-Eleven store in Claresholm.

The four were making a quick pit-stop on their way to the Calgary airport from Lethbridge so that MacLean and Craswell could fly home to P.E.I. for Christmas.

A crowd stands outside Winsloe United Church, just north of Charlottetown, at MacLean's funeral. (Ryan Hicks/CBC)

When they got back on the road, Jensen continued to follow the SUV for another 1.5 kilometres, then rammed it from behind. Conway was shot three times — in the abdomen, the thigh and shoulder — after getting out of the vehicle.

Jensen then shot the three others who were inside the SUV before turning the gun on himself.

The first of the four funerals was held Wednesday for Stepple, who was laid to rest in Lethbridge.

There was a steady stream of people at the Belvedere Funeral home in Charlottetown Wednesday for visitation for MacLean.

On Wednesday, MacLean's mother spoke publicly for the first time to pass on her gratitude for all the support her family has received.

"I just can't believe the support we're getting," Dianne MacLean told CBC News. "The support has just been, from all across the country ... all I can say is thank you."

Promising futures

Kevin Kvame, MacLean's baseball coach in Alberta, and several of the slain man's teammates flew to P.E.I. from Alberta for the funeral. (CBC)

Craswell and MacLean had promising futures in baseball. Both attended the Prairie Baseball Academy. They lived in Lethbridge with Kevin Kvame, the manager of their baseball team, the Lethbridge Bulls.

Kvame said Sunday the men were "two very important members of our baseball team that were fun to be around and terribly missed by their friends and families."

Teammates and coaches have said they've lost two top baseball players. MacLean was named rookie of the year and Craswell was an all-star shortstop.

Craswell had been celebrating his 22nd birthday the night before he died.

A memorial fund has been set up for MacLean and Craswell to help their families. According to a Facebook memorial page, any remaining proceeds will go towards a legacy scholarship fund for the men's teammates or any future players involved in the three organizations that set it up.