Brian Flynn was left to rue Simon Eastwood’s late flying stop which denied Rovers new-boy Dean Furman as his Doncaster side were held to a 1-1 draw.
The midfielder only arrived at the Keepmoat Stadium on loan from Oldham on Friday and was thrown on as a substitute just past the hour mark.
But the new man saw his hopes of a debut strike thwarted by the Blues goalkeeper who flung himself full length to palm away a drive from the edge of the box in the closing stages.
Rovers boss Flynn said: ‘Dean made a good debut and nearly got us the winner but their keeper made a fantastic save as it came through a crowd of players. He did really well to reach it.
‘But I still think it’s a point gained because I don’t think we were quite at our best.
‘I don’t think we functioned to perform our normal duties and roles.
‘We weren’t passing the ball well enough. I don’t think we had two consecutive passes that went forward.
‘We kept going backwards and that suited Portsmouth.’
While few would have predicted that top-of-the-table Rovers would have any trouble earning three points against relegation-candidates Pompey, Flynn was happy that results elsewhere meant his side extended their lead over their rivals.
He said: ‘Results elsewhere went for us, which is good but we can’t rely on other clubs.
‘We’re still in top spot and the challenge is to maintain it for the next eight games, whatever happens elsewhere.
‘We’ve taken four points out of the two games at Bournemouth away and Portsmouth at home and some people would be happy with that.
‘Maybe we’ve just done it in reverse.
‘But it keeps the momentum going. Everyone is working hard to get this club promoted and we will give it everything we’ve got between now and the end of the season to make sure it happens.’
– STEVE WILSON