CHICAGO (CBS) — An already porous Chicago Blackhawks defense is losing two veterans for the rest of the season, as both Brent Seabrook and Calvin de Haan will undergo surgery and be placed on long-term injured reserve.

De Haan has been out since leaving the Dec. 10 loss to the Vegas Golden Knights with a right shoulder injury. He will have surgery on Friday, and will miss the rest of the season.

Chicago Blackhawks’ Calvin de Haan (44) clears the pucks from the crease as goaltender Corey Crawford and Brent Seabrook (7) defend against Dallas Stars’ Jason Dickinson during the second period of an NHL hockey game Tuesday, Nov. 26, 2019, in Chicago. (AP Photo/Charles Rex Arbogast)

Seabrook hasn’t played since Dec. 15, and will have surgery on both hips; his right hip in early January, and his left hip in early February. He’s also finished for the year.

The Blackhawks’ defense already was ranked last in the league in shots allowed, with 36.1 per game, and was tied for 7th worst with 3.18 goals allowed per game.

Meantime, forward Brandon Saad will be out for approximately three weeks, after suffering an ankle injury on Dec. 19 when he was checked into the boards during a 4-1 win over the Winnipeg Jets.

Nearly halfway through the season, the struggling Blackhawks sit in the basement of the Central Division, and sit seven points back from the second wild card spot in the Western Conference.