Leinster’s prop problem has doggedly followed them around this year and, fittingly, has not gone away as they roll into the final week of the season with their squad depth continuing to be tested, especially on the loosehead side.With the news that Andrew Porter’s limping exit with a calf injury from Leinster’s semi-final win against the Stormers was as acute as some had expected, scrum coach Robin McBryde must again dig deep for their United Rugby Championship (URC) final on Friday in Croke Park against the Bulls (kick-off 7.30pm).It’s a challenge that has become familiar to the former Welsh hooker, who has the options this week of Alex Usanov, Jerry Cahir and Ed Byrne. It was Usanov who came on for Porter in the first half of the semi-final, with Cahir destined for Connacht next season and Byrne brought in for his experience on a short-term loan from Cardiff.Porter also missed the Six Nations with the same or a similar injury, while other options Paddy McCarthy and Jack Boyle have been sidelined long-term.Tadhg Furlong, who did not play in the URC quarter- or semi-finals, is fit for the tighthead side of the scrum, although hooker Dan Sheehan will be assessed later in the week along with captain Caelan Doris before the final team selection.“Losing Paddy [McCarthy] and losing Jack [Boyle] has put pressure on us to find talent elsewhere and whoever has worn that number one shirt or come on has done admirably with regards to Alex Usanov, Jerry Cahir, Ed Byrne, who has come back,” McBryde says. “We have managed it throughout the season.“It’s not ideal, but what it does is it grounds you as a coach because there are certain things that maybe you would want to do, but because of an injury or whatever you have got to stick to what is going to count.”The Bulls have one of the better, if not the best, scrum in the URC and, along with the lineout, McBryde expects Leinster to be tested by the South Africans. However, Porter brings more to a game that just his scrummaging. A dominant physical presence around the park, his tackling and ability to have an impact will be missed by Leinster, who are hoping for back-to-back titles, having beaten the Bulls 32-7 in Croke Park last year.“And Andrew is still maturing,” McBryde says. “His speaking is a lot more vocal in meetings and he plays a bigger role in the squad than previously. His personality is quite infectious.“He is pretty honest and down to earth and he doesn’t shy away from hard work, either. For him to suffer an injury with all the preparation and the professionalism around his character is tough for him. Andrew Porter is tackled by Marshall Sykes during Leinster's Champions Cup round of 16 match against Edinburgh in April. Photograph: Brian Lawless/PA “We will miss that stability and that experience, but we have been able to make up for those deficiencies during the season elsewhere. That’s why you call it a rugby team, that’s why you call it a pack. You’re not on your own. Hopefully that will be the case on Friday.”The Bulls have the powerful Springbok tighthead Wilco Louw in their squad, a test for any prop who is asked to step in. It is also worth remembering that Furlong was missing for last year’s final as Leinster dominated the game.“Yeah, I’d go along with that,” McBryde says about the quality of the Bulls scrum. “There’s no shortcuts, there’s no easy ways around it. You’ve just got to say, ‘This is what you’ve got to do to win the game’. There’s no shortcuts. “I had a great conversation with Rabah Slimani last week. He said, ‘When you look at your opposite number, if he doesn’t meet you eye-to-eye, if he goes early, if he doesn’t respect the referee’s commands, it just shows you he’s scared’. “So we can’t be scared. We’ve got to meet them head-on and go for it.”Leinster learned harsh lessons losing the Champions Cup final to a rampant Bordeaux Bègles and they’re hoping that pain can help make Croke Park a success.“If you don’t learn from that, then it’s just a wasted experience,” McBryde says of the defeat.The team unpacked the game last week because after the Bilbao final they were straight into their URC quarter-final. McBryde acknowledges there were some difficult discussions because of the way the match unfolded. The Champions Cup defeat also dovetailed with what he calls a “messy” season with regards to Leinster not finding their flow on a consistent basis. Despite that, McBryde senses plenty of determination in the squad. “From my point of view, adversity introduces a man to himself,” he says. Leinster can expect much more of it on Friday.