For years, NFL coaches thought most rookies should be neither seen nor heard on game days. Less experience meant more mistakes which meant a greater chance that coaches would be fired. But times are changing. For a variety of factors, rookies are far more likely to start games than they were five years ago, and Cardinals fans can expect to witness the trend this fall. Coach Bruce Arians isn’t afraid to play rookies, players he believes are better prepared than ever before. Under the collective-bargaining agreement, there are limits to the number of hours veterans can spend at a team facility in the off-season. Most rookies, in contrast, can spend more time than veterans in meetings and on the field. “They are getting so many more repetitions and exposure to the coaching staff that they’ve never gotten before,” Arians said. “You can get them ready to play. “In the past if you had 10 OTAs (organized team activities) they might get 35 reps the entire time. Now, they’ll come up with as many as 200, and hours and hours of meeting time.” Statistics back up Arians. According to the Elias Sports Bureau, NFL rookies started 707 games in 2008, and the number has increased steadily since, to 772 in 2009, to 865 in 2010, to 921 in 2011 and to 998 last year. Rick Gosselin of the Dallas Morning News broke down the statistics from 2012. The Browns had 87 games started by rookies to lead the NFL. The 49ers were last with zero. The Cardinals were 15th with 32 rookie starts, and the Colts, where Arians was the offensive coordinator and interim coach, had 55 last season. The Colts started rookies out of necessity. The franchise was making over its roster, and Colts veterans suffered an uncommon number of injuries during the season. “It was an unusual situation,” Arians said. “We were drafting starters. We had one tight end on our roster.” The Cardinals numbers have trended up in recent years, too. They had 18 starts by rookies in 2008, three in 2009, 35 in 2011 and 32 a year ago. That, too, was partly out of necessity. Some key veterans — receiver Anquan Boldin, linebacker Karlos Dansby and safety Antrel Rolle — left via trade, free agency or released. For the most part, they were replaced by younger, cheaper players. It would be easy to blame the team’s problems over the past three years on the youth movement, but in many instances, it was the veterans who failed.