Though the Canucks led by four goals late in the second period, Washington rallied late and beat Vancouver 6-5 in a shootout.
''It's a 60-minute hockey game for a reason and (Washington) won the Stanley Cup for a reason,'' Horvat said. ''They've got some good players over there. We had to play a full 60 to beat that squad.''
Tim Schaller scored twice for Vancouver, Brock Boeser had a goal and an assist, and Elias Pettersson and Jake Virtanen also scored.
Jacob Markstrom had 24 saves for the Canucks.
Vancouver scored three times in the second period and led 5-1 with less than a second remaining in the period.
Schaller scored his second of the game 13:59 into the period, batting a rebound out of the air and into Washington's net.
It was the Canucks forward's third goal of the season, matching his total of last year when he finished with 10 points (three goals, seven assists).
''My mentality's been get pucks to the net one way or the other,'' Schaller said.
Still, settling for a single point on Friday night was frustrating, he added.
''Just one more blocked shot, one more puck deep would have got the job done,'' he said. ''They came hard and we played well enough to win, but they just had one more bounce than we did.''
Nicklas Backstrom sealed the comeback for Washington, beating Markstrom on the stick side in the third round of the shootout.
Evgeny Kuznetsov and Michal Kempny each scored two goals for the Capitals in regulation. Lars Eller added a goal and an assist.
Goalie Ilya Samsonov stopped 29 of 34 shots for Washington in his fifth start of the season.
It was a big performance for the rookie goaltender, Capitals coach Todd Reirden said.
''They converted on some mistakes by us, he still made some big saves in the third and overtime and great to see him in the shootout,'' he said of the 22-year-old Samsonov.
''He just looks so comfortable back there, give up a goal or doesn't give up a goal, it doesn't really change how he acts, which is a rarity for young goaltender and a special presence he has. He has a really bright future ahead of him.''
Finishing strong Friday was a big deal for Washington, Kuznetzov said.
''I feel like these types of moments, they build the team spirit and build the team together and that's huge for us,'' said Kuznetzov , who put a wrist shot past Markstrom with just 0.3 seconds left in the second period to get the comeback started.
''Get back from 5-1,that means a lot for guys,'' he said. ''We stick with each other, we stick to the game plan even though the game never went well, we give up some bad goals, but we stick with our plan and we get the results.''
Reirden felt that Kuznetsov's late tally gave his group something to work with heading into the third.
''We were able to talk about that between periods and really feel like we could build some momentum and get some opportunities if we played the right way,'' he said. ''We didn't feel like we needed to cheat to get the offense but we thought we could get some chances.''
Washington scored three goals on six shots in the game's final period, and was outshot 32-22 by the Canucks in regulation.
During a timeout midway through the third period, Canucks coach Travis Green reminded his team to breath and pointed out that they weren't being hemmed in their own zone.
He encouraged them to get back on the ice and win the final minutes of the contest.
''We were probably the better team the last 10 to 12 minutes of the game,'' he said. ''But this is one game. We got a point. We definitely wanted two. ... You play 82 games and you've got to learn from every one of them.''
NOTES: The Capitals were coming off a 5-4 overtime loss to the Edmonton Oilers on Thursday night. ... Washington defenseman John Carlson saw his nine-game point streak snapped on Friday. He continues to lead the league in scoring with 21 points (five goals, 16 assists).
Capitals: At Toronto Maple Leafs on Tuesday.
Canucks: Host Florida Panthers on Monday.
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