Bagley will need to keep up his momentum at the free throw line. Key three: Duke needs to improve from deep in the PK80 Invitational After starting off the season 5-0 against lesser competition—outside of a thrilling win against No. 2 Michigan State—Duke will face stiffer opponents in this week's PK80 tournament in Portland, Oregon. If the Blue Devils beat Portland State Thursday, it would play the winner of Butler and Texas Friday before potentially taking on either No. 7 Florida or No. 17 Gonzaga on Sunday. The Blue Zone gives three keys for this week's tournament: Convert from deep After losing Luke Kennard and Jayson Tatum to the NBA, the Blue Devils have struggled to connect from beyond the arc so far this season. Despite shooting better than 40 percent from downtown in its first two games, Duke has gone ice cold—converting on just 24 percent of its looks in two contests over the last week. While the Blue Devils have been able to dominate on the interior to compensate for imprecise shooting, Duke will likely not be able to drive with ease this week against bigger teams like Texas and Florida, which could put pressure on Gary Trent Jr. and Grayson Allen to get back on track from the perimeter. Cash in at the stripe In 2016, Duke converted on 76 percent of its free throw attempts, and frequently used its clutch free throw shooting to shorten games, especially during its ACC tournament run. While the Blue Devils haven’t relied on their free throw shooting to win them games this season, Duke will need to be better from the line in order to beat teams like Florida, Butler or Gonzaga this weekend. The Blue Devils have made a mere 62 percent of their attempts from the charity stripe— currently tied for 323rd out of the 351 teams in Division I—and especially need star big man Marvin Bagley III and guard Trevon Duval to convert better than their respective 50 and 58 percent clips from the line. Bagley made progress against Furman, knocking down 5-of-6 attempts, while Duval didn't attempt a shot. Continue to dominate the glass Perhaps the Blue Devil's biggest improvement this year has been their ability to dominate the offensive glass. Thanks to the additions of Bagley and fellow freshman Wendell Carter Jr., Duke has brought in 17.6 offensive boards per contest—good for third in the nation—and has used those second chances to generate more than 90 points a contest. The Blue Devils will need to continue this dominance in Portland this weekend against some other strong glass crashers. Portland State ranks second in the nation with 18.0 offensive rebounds per game and 6-foot-11 Texas freshman center Mo Bamba has added 18 boards in his ledger over his first two career contests.