EL SEGUNDO (CBSLA.com) — The victim in Wednesday’s murder-suicide at UCLA was a mechanical and aerospace engineering professor.

William Klug, 39, was shot and killed by a disgruntled student, who was despondent about his grades, police said.

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The father of two lived in El Segundo and coached his son’s Little League team. He was planning to attend Wednesday night’s playoff game at a park at Pine Avenue and Sheldon Street.

But parents had to explain to the players and the community that their coach was no longer with them.

“He would have wanted the boys to play tonight without a doubt,” the victim’s friend Peter Gianusso said. “He loved baseball.”

His friends described him as a calm, quiet man with a passion for learning and teaching.

“It’s just very, very sad to hear this,” Klug’s close friend, Lance Giroux said. “Never a negative word. Always very positive. Kids loved working with him because he was such an easy coach to work with.”

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Devastated students and colleagues shared their grief on social media.

Klug’s friends said they must now focus on the family he left behind, especially his two children who have to grow up without their father.

“To have your son grow up without a dad is rough,” Giroux said as he fought back tears. “So, I’m hoping the community here can kind of rally around that.”

According to his online biography, Klug earned a bachelor’s degree from Westmont College in 1998, a master’s at UCLA in 1999 and a doctorate from Caltech in 2003.

Friends plan to honor Klug during the final game at the park on Saturday.

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A gofundme account has been set up to help Klug’s family. Click here if you would like to help.