BRIAN O'DRISCOLL believes Jordie Barrett should have started ahead of Robbie Henshaw against Northampton Saints. And the Ireland legend said the decision to leave the All Blacks star on the bench "didn't make sense". Eyebrows were raised when Barrett - signed last December on a short-term deal - was named amongst the subs for the Champions Cup semi-final. The decision backfired, as Leo Cullen's men were beaten 37-34 at the Aviva Stadium to inflict more European pain on the province. Speaking on Off The Ball, O'Driscoll suggested Barrett should have started at centre over Robbie Henshaw He said: "I was in a WhatsApp group with a couple of ex-teammates and the conversation at half-time was, 'how can you get Jordie Barrett on without it coming across as panic stations?' It is so true. "Robbie wasn't having a terrible day but what Jordie Barrett has brought to the club, the performances he has had, the punch he gives is another dimension to Robbie's game. That is the reality. "I thought he was very good when he came on and he gave that go forward and brought that huge physicality. "It is something that they are going to have to live with and the criticism is fair because I think they got it wrong. "I've seen so much written about hands being tied around playing both players together and it is a tricky one having two international centres and bringing in an All-Black centre, but the reality is I think when it comes to semi-finals and finals, you have to pick your very best players in form. "What must he have been thinking while the game was playing on, thinking I am not out there and I could really be doing a job. "Are we saying that it would have been different had he been out there? We will never know, but play your best players. "He is a marquee signing. Don't bench him for semi-finals and finals, that makes no sense. "Is he playing better rugby than Robbie Henshaw at the moment? Yeah I think no one would disagree with that, including Robbie. "I don't think Robbie would have had any problem being on the bench knowing how Jordie has played recently. "I think that was a mistake." The New Zealand international was not the only high profile replacement, with Andrew Porter also on the bench. The Ireland prop was eventually introduced for Cian Healy, but O'Driscoll was left baffled by the decision not to pick him from the start. He said: "I must say Andrew Porter not starting for me doesn't make sense either. He is a 75 minute international regularly. "What he brings you in the loose is phenomenal. I am not saying that just because Cian missed the jump on the [Will] Freeman first try. "Play your best team up front. I have never been of that mindset around we need to be loaded for the second-half. "It is easy retrospectively to say they had 12 points to catch up in the second-half and it is a lot of work to do and they do win the second-half 19-10 or whatever it was but don't put yourself in that position in the first place. "Leinster have put teams out of sight a lot by playing their best team. "I am not saying they were going to do that against Northampton but I have never been a subscriber to holding back better players on a bench and I don't think I ever will be."