DAVID O'Brien says only time will tell if title rivals Partick Thistle are affected by the recent departure of manager Jackie McNamara.

McNamara and assistant Simon Donnelly were unveiled as the new Dundee United management team on Wednesday afternoon.

As a result, experienced Jags centre-half Alan Archibald has been installed as interim boss at Firhill and will be assisted by former Morton defender Scott Paterson.

Ton wideman O'Brien, who turned 29 last Thursday, admits McNamara's departure left him shocked but insists there's no way of telling if the change will benefit the Cappielow club.

He told the Tele: "I was a wee bit surprised to hear the news because I thought he would maybe have wanted to stay with Partick and tried to win the league.

"It's hard to say what effect that will have. I don't really know any of the boys at Partick to speak to them about their thoughts.

"I'm sure a lot of them will be devastated he's left because they've had a pretty good season so far.

"But other boys might be happy, you just don't know.

"They could bring a new manager in and change their style of play but I think they're talking about keeping it the same with Alan Archibald taking over.

"We'll maybe see in the next few games how that affects their season, if at all. Only time will tell.

"At the end of the day we just look at ourselves.

"We've got a really good squad, we're all happy and we're doing well, so that's our focus."