And he predicted Ally McCoist's men will get back to their best against Albion Rovers in the William Hill Scottish Cup on Sunday.
The SPFL League One leaders struggled to overcome Stranraer at Stair Park last Tuesday and then East Fife at New Bayview on Saturday.
But centre-half Mohsni reckoned the dire quality of the playing surfaces in Stranraer and Methil were to blame for the below par showings.
And the French-Tunisian defender is confident Rangers will perform better when they return to Ibrox in the cup quarter-final this weekend.
He said: "Some of the away pitches are disasters. You have to concentrate very hard on your first touch when you play on them.
"But because you concentrate on your first touch you forget the player presses you. It makes it hard.
"Of course, it's the same for both teams, but the pitch definitely doesn't help.
"The other clubs in our league don't have the same budget as us. It's normal and we expect it.
"The playing surface at Ibrox is better so hopefully our performance will be better this weekend."
Mohsni added: "All of the team played nearly 90 minutes on Tuesday and then on Saturday. The legs become tired as a result.
"This is why we're not playing as well as we have earlier in the season.
"But we won both of the games and that's the most important thing. We didn't play well, but we came from two away games with six points.
"We will not treat Albion Rovers lightly this weekend, but we are at home and hopefully we can play far better against them than we have done away from home."
Meanwhile, Mohsni has insisted his relationship with Rangers keeper Cammy Bell is good despite their on-field bust-up against Stranraer.
Mohsni and Bell got involved in a screaming match in the first half of the League One match in Wigtownshire after a breakdown in communication.
The goalie afterwards claimed that flare-ups were healthy for the team and underlined their desire to perform well.
And Mohsni has now stressed that he has not got any problem with the former Kilmarnock and Scotland player.
He said: "Everyone wants to do better. I tried to hold the striker and expected Cammy to come and take the pressure off.
"But Cammy saw it another way. Sometimes it happens in football.
"But Cammy and I are fine. He had three great saves in the match.
"After the game I apologised. He was right in one way and I was right in another. You can't tell another player how to do his job."