Jeremy Corbyn and Owen Smith may belong to the same party but the two cut different figures during their first Labour leadership debate - which took place in the All Nations Centre in Cardiff on Thursday evening.
Here are five key clashes of the evening.
1. Party unity
Corbyn kicked off the tete-a-tete by taking a pop at the mass Shadow Cabinet resignation, which culminated in a bid to topple him as leader, and rounded on Smith for being one of the Labour rebels. Smith was jeered by Corbyn supporters at several points after calling for unity in the party.
2. EU referendum
There were subtle differences in the pair's views on the EU - with both hammering home the point of how the European Union was good for Britain. However, Corbyn, who discussed the pros and cons of Europe, received a few boos from the crowd after saying Article 50 would have to be implemented. Smith, on the other hand, said Britain should have a second referendum and talked about how bad Brexit would be for Britain.
The issue of Britain's nuclear deterrent and whether to renew it was perhaps the biggest sticking point of the night. Famed CND campaigner Corbyn stressed how futile nuclear weapons were - and that spending billions of pounds on something that would cause mass destruction to the planet was a waste of money and also a threat to peace. Corbyn claimed Britain could send a message to the world and aid global disarmament by getting rid of its nuclear weapons. However, Smith called his rival "naive" and said the world was becoming more volatile and the UK's security was improved by having nukes.
The controversy surrounding alleged anti-Semitism among a minority in the Labour Party surfaced during the debate and saw both contenders heckled loudly during their respective answers on how to tackle the issue.
Following 90 minutes of call-and-response debate, at the end of the clash both candidates were given two minutes each to say why they would make the best leader. While Smith drew large applause after his polished address, it was Corbyn who gained a standing ovation.