Rangers manager Steven Gerrard admits his starting formation was unsuccessful in Saturday's win over St Mirren but vowed to keep experimenting.

Gerrard reintroduced the midfield diamond formation he employed in the recent defeat by Kilmarnock as January signings Steven Davis and Jermain Defoe began the match after being left out of the starting line-up in the previous weekend's win over Livingston.

Rangers won 4-0 but with the help of four spot-kicks – three of which they scored from – in a controversial display by referee Andrew Dallas.

Gerrard told Rangers TV: "I don't think the diamond worked again at the weekend but I don't think any system is going to work if you don't have that intensity or aggression in your play.

"I felt when we went to a 4-4-2 in the second half at the weekend we looked a lot better, we had a bit more balance and Ryan Kent certainly looked more dangerous out on the left.

"You learn all the time with players individually and collectively but certainly having Jermain around does give us more of a threat and gives us the chance to play two forwards on the pitch, which is what we're going to need at times."

Ahead of Wednesday's trip to Aberdeen, Gerrard added: "It is my job to keep oppositions guessing. There was times when we played the 4-3-3 system before the winter break where we were looking like we needed more of a threat on the pitch.

"We went to a 4-4-2 against St Johnstone when (Kyle) Lafferty came on and he made a big difference and gave us more of a threat up top.

"We have got options to do that but I won't be playing 4-4-2 every week or four-diamond-two every week. We do have to have flexibility in our game if we want to be successful."