A porous defense prevented the Calgary Flames from a return playoff trip, while a sporadic offense is a main reason why the Vancouver Canucks won't be playing beyond this week.

Both teams enter Thursday night's matchup off disappointing results that can be attributed to each's main weakness.

Calgary (33-40-7) heads into its home finale tied with the Canucks for 12th in the Western Conference and having allowed a league-high 256 goals. It's permitted four or more five times during a 2-5-1 stretch that dashed an already minuscule chance of a second consecutive postseason berth.

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The Flames did deliver one of their best defensive performances in Saturday's 5-0 victory at Edmonton, but their bad habits returned Tuesday against Los Angeles. Calgary twice blew a third-period lead in a 5-4 overtime defeat, with the Kings forcing extra time on Kris Versteeg's goal with 35.1 seconds left in regulation.

It's a familiar outcome for a team that failed to build off last season's surprising 97-point output despite a 30-goal sophomore campaign from Johnny Gaudreau, a second straight strong season from fellow youngster Sean Monahan and an injury-free one from captain Mark Giordano, who scored his 21st goal Tuesday to record the highest total for a Flames defenseman since Al MacInnis' 28 in 1993-94.

"Every guy in this locker room that is having a career year would much rather replace it to be in the playoffs and be playing for the Stanley Cup." Gaudreau told the Flames' official website.

Vancouver (30-37-13) will miss the playoffs in large part due to ranking 29th in the NHL with 180 goals.

The lowest point occurred during an 0-8-1 run from March 14-29 in which the Canucks mustered eight goals and were shut out four times. They rebounded to win a season-high three straight prior to Wednesday's 6-2 defeat to an emotionally charged Edmonton team playing its final game at Rexall Place.

Vancouver trailed 3-0 after two periods before goals from Matt Bartkowski and Bo Horvat avoided a 10th shutout loss this season.

"I thought we'd have a little more intensity in our game," coach Willie Desjardins said. "We accepted being average. We didn't fight through enough."

The Canucks did score at will in a season-opening 5-1 victory at the Saddledome on Oct. 7 but totaled five goals in losing the series' past three matchups, including a 5-2 setback at Calgary on Feb. 19.

Jonas Hiller was in net for each of those wins but will give way in this game to Joni Ortio, who attempts to bounce back from Tuesday's 21-save effort. The 24-year-old had posted a 1.82 goals-against average over his previous six starts and had 28 saves against Edmonton for his second NHL shutout.

After Jacob Markstrom struggled in Wednesday's loss, the Canucks turn back to Ryan Miller. The veteran recorded his second consecutive win with 40 saves in Monday's 3-2 victory over Los Angeles.

Miller has yielded six goals in three 2015-16 meetings with Calgary and stopped 29 of 30 shots in the season opener.

Horvat enters the matchup with three goals and two assists over a four-game point streak.