DON'T!!!!! He's crawling to cover because he was out in the open and got shot down. The person who shot him is waiting to see if you'll be a hero so they can shoot YOU! Maintain situational awareness. Notice where the gunfire is coming from and get to the nearest patch of cover. Crouch. If they're headed towards you, they'll get the hint. If they don't get the hint or bleed out before they get to you, their death didn't cost your team two lives. If they can get into cover, THEN rescue them and get them to an Apothecary/Pain Boy/Warlock/Sorceror quick, fast, and in a hurry. If you ARE a medic, avoid the temptation to range heal them, as standing up takes FOREVER in this game and the shooter will just shoot him AGAIN, recreating the problem but without the armor/health they had the first time, possibly resulting in an insta-kill. This is the number one reason people have died trying to rescue me, and if I could yell at them without yelling at the entire area I would every single time. If I know I can't make it to cover I'll just bleed out, and I can wait the few extra seconds to get back into the war. Thank you, and good Crusading!