Jared Cowen started the season last week on the Ottawa Senators top defensive pairing with Erik Karlsson.

But just a few days later, Cowen was a healthy scratch for the club's 1-0 win over the Florida Panthers on Monday night - a decision the defenseman admits caught him a little bit off guard.

"Yeah it surprised me. Only two games, so yeah it did surprise me," Cowen admitted to reporters on Wednesday afternoon. "It sucks only the third game of the year. I just need to be better though."

It looks like Cowen may be a healthy scratch again when the Senators host the Colorado Avalanche in their home opener on Thursday night. Based on the way the club ran practice on Wednesday, Cowen appears to be the odd man out once again. Paul MacLean did not confirm his lineup for Thursday's game against the Avalanche, but all signs point to Cowen being out of the lineup at this point.

"Right now Jared needs to come to the rink every day and continue to work at his game. He's still a young player in this game -- just over 100 games - so there's still a lot to learn. There are still lots of good games left in Jared Cowen. There's like 900 games left in him," MacLean told the media. "Sometimes it's hard to be that age and we don't want him to accept that you're being scratched from games. But we expect you're going to come in and work with us to become a better player because that's what it's all about."

Cowen saw only 13:37 of ice time against the Lightning on Saturday night and was benched for the majority of the third period and overtime after he was on the ice for Tampa Bay's tying goal. While Cowen thought he played a decent game in the opener in Nashville, he admitted his performance against the Lightning left something to be desired.

"Tampa wasn't as good. Hard to put your finger on it, but I think looking back on it, you just want to do your job and not worry about anybody else. Take care of the simple things and then after that, the game comes to you."

Both Cowen and MacLean dismissed the notion that being partnered with Karlsson has contributed to his early season struggles. Karlsson is an offensive-oriented defenceman who doesn't always play a traditional game on the back end, which could make him a tough partner for some defencemen.

"I've played enough with him where I know what he's going to do and his tendencies to be able to figure it out. It's not rocket science. He is uncharacteristic of most players, but it's nothing that I shouldn't be able to handle," Cowen said.

MacLean reiterated on Wednesday that the defenceman he takes out of the lineup will have a left-shot - meaning that Cowen and Patrick Wiercioch remain the most likely candidates to be scratched at this point.

Cowen is under the microscope this season, as he tries to bounce back from a subpar 2013-14 campaign which coincided with him signing a four-year contract extension worth $12.4 million. The 23-year-old says that the mental aspect of his game is just fine, despite the limited playing time in the first week of the season.

"Yeah, I have confidence, it's just getting games going and shifts and rhythms. In Nashville I felt like I was getting that, but in Tampa not really, not on and off the ice.

Cowen also says he's no longer feeling any effects of hip surgery from the fall of 2012 - a significant injury that stalled his development after a banner rookie season in 2011-12.

"I think last year I was feeling good at this point, but once the games got going it started to wear on me. But I don't think that's going to happen to me this year. I feel stronger, fitter, and more capable of playing the whole season," said Cowen.