National Hockey League roundup

Louis Blues forward Jaden Schwartz will miss at least four weeks and the start of the regular season after injuring his left elbow during practice.

The team announced Friday that Schwartz suffered the injury Thursday.

Schwartz, 24, appeared in 33 regular-season games with the Blues in 2015-16 after fracturing his ankle last October, posting 22 points (eight goals, 14 assists).

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President Barack Obama will welcome the Pittsburgh Penguins to the White House next week to honor the 2016 Stanley Cup champions.

The gathering on Thursday will be the Penguins' second visit with President Obama. The Penguins first met the president after winning the Stanley Cup in 2009 during his first term.

"I started off my presidency with a Penguins Stanley Cup, and I'm now ending it with a Penguins Stanley Cup," Obama said during the June phone call to head coach Mike Sullivan.

The Penguins captured the title with a six-game finals win over the San Jose Sharks.

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The Chicago Blackhawks agreed to terms with forward Graham Knott on a three-year contract.

Knott was drafted by the Blackhawks in the second round (54th overall) of the 2015 NHL draft.