I guess, you know, somebody that s 7 years old playing the piano and you kind of show them, they hear it, and then they start playing the piano, Roman said. It s one of those things that if you can explain it to him, once it clicks with him and that s happened repeatedly on a lot of different things he just makes that adjustment, and we keep moving. Coach Jim Harbaugh is careful not to compare players but made an exception with the running back who was drafted in the second round. Carlos gets football, understands football; it s natural for him to understand the game, similar to Frank Gore, he said. And we re seeing those things, and both are very good signs and bode well for us. As a rookie, Hyde already was destined for a sizable workload during training camp and the preseason as the 49ers try to keep Gore, 31, as fresh and healthy as possible for the regular season. Hyde s summer school session, however, intensified when in short succession the 49ers lost two tailbacks ahead of him on the depth chart.Kendall Hunter tore a knee ligament and will miss the season. LaMichael James dislocated his elbow and could miss several more weeks. Another runner, Marcus Lattimore, has not been cleared for practice.That leaves Hyde, 2013 practice-squad player Jewel Hampton and newcomer Alfonso Smith as Gore s backups.In recent years, when the 49ers have needed a change of pace from Gore, they ve gone with a small runner. Hunter is listed at 199 pounds. When Hunter tore his Achilles tendon in 2012, the role was filled by James, who at the time was about 190 pounds. James could be Gore s top backup again this year. He is expected to return more than a week before the 49ers opener in Dallas on Sept. 7.But Hyde has to be an intriguing option for the 49ers. At 235 pounds, he s easily their biggest tailback. But he has the maneuverability of a much smaller man. He s got very quick feet, and he s very smooth, rookie linebacker Chris Borland said. There s no hesitation in breaks. He looks like he s 205 (pounds). Borland is somewhat of an expert on the subject. When his Wisconsin squad played Ohio State last year, the objective was to stop Hyde. Was it a success?Hyde rushed for 85 yards, the only full game he played last season in which he rushed for fewer than 100 yards. But teammate Braxton Miller ran for 83 yards, and the Buckeyes won 31-24. It s kind of pick your poison, Borland said. And we tried to stop Carlos, and Braxton had a great game. That s kind of how it works. Hyde averaged 155 yards and nearly two touchdowns in the nine games after Wisconsin. He said his style isn t complicated. I m a hard-nosed runner, a guy that just runs with a lot of passion, relentless, Hyde said. (I) refuse to go down. He also shed some light on how he s been able to pick up the 49ers approach so quickly. I actually sit behind (running backs) coach (Tom) Rathman, so I m able to whisper in his ear about protections and stuff, Hyde said. What s going on here? Why did Frank do that?