CHICAGO -- Here are three takeaways from the Chicago Blackhawks’ 5-4 overtime win over the Detroit Red Wings on Tuesday in Chicago's preseason opener:

1. Scott Darling will give the Blackhawks one of the league’s better backup goaltenders this season. Darling was extraordinary against the Red Wings during his one-and-a-half periods of action. His size is always an advantage, but he’s more than that. The Red Wings tested him in every which way Tuesday, and he was up to the challenge every time. Darling was especially impressive when he was forced to make consecutive saves. During one sequence, he poked the puck away from a Red Wing, was knocked to the ice by that same player and then made two saves while on the ground. Altogether, he stopped 22 of 22 shots. Blackhawks coach Joel Quenneville described him as “great” after the game. Darling said in the dressing room afterward that this season he is out to prove he’s not a “one-hit wonder." So far, he’s doing a good job of that.

2. The Blackhawks’ biggest remaining question is the last few defensemen. Trevor Daley can skate and has ability, and the Blackhawk know what they have in Duncan Keith, Brent Seabrook and Niklas Hjalmarsson. After that, it’s still up in the air. David Rundblad played against the Red Wings on Tuesday, and he again struggled in the defensive zone. He was on the ice for all three of the Red Wings’ 5-on-5 goals. He wasn’t completely to blame for the goals, but it was more than just a coincidence. Quenneville was asked about Rundblad in the postgame press conference, and he didn’t assign any blame to Rundblad. Quenneville said he would look at the game film and see if there were adjustments to be made.

3. It’s early, but all signs are pointing to Teuvo Teravainen having a massive second season. He is more confident on and off the ice, and he has grown into his body. Teravainen showed again Tuesday his ability to carry the puck in all zones, see the ice differently than most and be defensively responsible. He and Patrick Kane didn’t score in 5-on-5 play, but there were times when they seemed like the only two players on the ice, with the way they played off each other and made passes. Quenneville likely won’t keep them together because he feels splitting them apart creates more balance, but there is a chance they could be united on the power play. That’s also where Teravainen will make a difference this season. The Blackhawks’ power play could actually be a threat with Kane and Teravainen creating. You can tell in the dressing room that Teravainen is also more comfortable speaking English and talking to the media. He’s no longer that shy Finnish rookie.