"We have to work and finish the season with a bit of pride, which is what we're aiming to do.
"Next year, in the off-season, pre-season, we're going to have to work a lot harder on being able to concentrate in the game.
"That's through conditioning - physical conditioning and mental conditioning and making sure we become a tougher team.''
Two defeats in this shocking run for the Warriors came against Newcastle and Manly came after they had built 18-point leads.
"I think in general, we've been too inconsistent in our form - through games and throughout the season,'' McClennan said.
"There have been periods, like the period against Manly, to get out to 18-0 playing some really good football - then we slacken off with 30 seconds to go [in the half] and let them back in.''
The Cowboys scored at a point a minute in the first quarter of the match, with Carlos Tuimavave finally responding with a try for the Warriors and his side went to the halftime break 22-6 down.
Winger Manu Vatuvei scored his 100th NRL try when touching down after the break but it was a rare positive moment for the Auckland-based team who are 13th on the ladder. Another happened before kick-off when James Maloney was given the all-clear following an against-the-odds recover from his knee injury.
For the Cowboys, winger Ashley Graham scored a hat-trick and Johnathan Thurston and Matt Bowen predictably ran the show.
Warriors' fullback Kevin Locke's involvement for the rest of the season is in doubt after he injured an ankle in the first half.
Cowboys 52 (Ashley Graham 3, Matt Bowen, Antonio Winterstein, Kane Linnett, Gavin Cooper, Brent Tate, Aaron Payne tries; Johnathan Thurston 8 goals). Warriors 12 (Carlos Tuimavave, Manu Vatuvei tries; James Maloney 2 goals). HT: 22-6