Beyond the symbolism of Opening Day, Jeff Samardzija knows the Cubs have to get off to a fast start. Or else. Because this front office isn’t going to hesitate if it looks like they should be sellers at the trade deadline. After Friday’s 6-2 loss to the Arizona Diamondbacks at HoHoKam Stadium, Dale Sveum played it coy again and wouldn’t reveal who will be starting on April 1 in Pittsburgh. But at this point it would be a major upset if the manager picks anyone other than Samardzija, who wants the responsibility that comes with being a No. 1 starter. Whenever Samardzija takes the ball, he will feel a real sense of urgency, understanding that the first six weeks or two months could determine the entire direction of the 2013 season. “Without a doubt,” Samardzija said after three up-and-down innings. “It’s very, very important, especially with guys like (Matt) Garza and these different dudes that are about to be free agents. “We need to show that when they’re on this team, we’re a more capable team – to win games and make the playoffs and go from there. That’s for us to prove on the field. And as long as we can do that, then you can add pieces instead of taking them away.”