Michael Appleton praised his Pompey players for keeping their cool in tough circumstances at Crawley.
Goals from Ashley Harris, Luke Rodgers and Izale McLeod earned the Blues a 3-0 win after the home side had two players sent off.
It left the Crawley fans baying for blood but Appleton was impressed with the way his men gave the referee no decisions to make as the atmosphere reached boiling point.
He said: ‘I’m glad we kept our discipline.
‘They lost their discipline and we put in a controlled performance to get the win.
‘We’re delighted with the result and can push on now.’
Appleton did not feel the two dismissals were the decisive factor and was happy with the display from the Blues.
‘The lads knew the importance of the three points and I felt we were positive,’ he said.
‘It was always going to be our day.
‘Even in the first half, they had a lot of long balls and crosses but I felt we dealt with it well.’