The 49ers head to training camp this week chastened by a 2007 campaign that fell well short of expectations but optimistic after a busy offseason. The team brought in big names on offense and defense, starting with former Bengal Justin Smith. The 280-pound Smith will assume a playmaking role at defensive end as well as fill the leadership void left by Bryant Young, who announced his retirement last season. The 49ers also augmented their defensive line with first-round draft pick Kentwan Balmer, the first lineman drafted by the Mike Nolan regime who truly fits the 3-4 defense the coach has wanted to run since he arrived.

On offense, the 49ers found two starting-caliber wide receivers in free agency, and better yet, plucked them from division rivals. Longtime Rams star Isaac Bruce was brought in for his leadership while Bryant Johnson is finally out of the shadows of former Cardinals teammates Larry Fitzgerald and Anquan Boldin.

The 49ers' biggest addition, however, was to the coaching staff.

The team's 2007 offense was so bad and so boring that at times it was hard to watch. In offensive coordinator Mike Martz, the team added a man whose name is synonymous with creative and high-scoring attacks. The 49ers hope that if they fix their problems on the offense, perhaps the lofty expectations they had in 2007 won't seem so unrealistic.

If the problems aren't fixed? Nolan's fourth season in San Francisco might be his last.

WHY THE 49ERS WILL IMPROVE

The Martz effect

In the two years Mike Martz was in Detroit, the Lions' offense jumped from 27th in the league to 19th. If the 49ers experience a similar lift, the team's overall fortunes should improve dramatically. Perhaps the best sign is that Martz isn't forcing the 49ers, long a power-rushing team, to adhere to a new formula. Martz recognizes the team's talent at tailback and tight end, and he is tailoring the system to those strengths. In San Francisco, Martz has the rushing attack, offensive-line talent and defensive support he lacked with the Lions.

Willis, part two

Last season, rookie linebacker Patrick Willis was the scourge of offenses, chasing down ballcarriers in every corner of the field. He finished the season with a league-leading 174 tackles, 33 more than the second-place finisher. His run-down of Cardinals wide receiver Sean Morey, a tackle that kept the 49ers alive in an overtime contest they ultimately won, was the play of the year for San Francisco. And yet Willis says his performance was not good enough. If he adds turnovers to his repertoire, the 2007 Defensive Rookie of the Year could be looking at Defensive Player of the Year.

On the hot seat

After the 2007 season, the Yorks decided to retain coach Mike Nolan for a fourth season. A fifth, however, is a long shot unless the team improves dramatically. That pressure should prompt Nolan, who has a conservative tendency, to give Martz free rein with the offense.

WHY THE 49ERS WILL STRUGGLE

Two's a crowd

The 49ers have a quarterback conundrum, and they haven't even reported for training camp yet. Alex Smith and Shaun Hill will continue to share snaps in practice, and Nolan said a starter won't be picked until the third exhibition game against the Bears on Aug. 21. Even then, the winner of the competition could lose the job before opening day, Nolan said. While that pressure is designed to squeeze the most out of the team's passers, it also could hurt if the starter is constantly looking over his shoulder and trying to avoid mistakes. Should the starter struggle, everyone – from the media to the players to the starter himself – naturally will look to see if the backup is warming up.

Where's the rush?

The 49ers have three primary edge pass rushers – defensive end Justin Smith, linebacker Manny Lawson and linebacker Tully Banta-Cain. All are decent, but not one has registered double-digit sacks in his career. Without a true sack artist, the 49ers again will have to engineer their pass rush, a situation that puts pressure on even the best secondaries. As games last season against the Saints' Drew Brees and the Cardinals' Kurt Warner proved, the 49ers' defense can't afford to give opposing quarterbacks time to throw.

When egos collide

The 49ers have a conservative, defensive-minded head coach and a risk-taking, iconoclastic offensive coordinator who used to be a head coach. Both men have strong personalities. Both crave control. So far, the relationship between Nolan and Martz has been cozy and cordial, and both coaches realize their own success hinges on the other man. But with a head-coaching job on the line – for both men – who knows what will happen should the team struggle.

CAMP FACTS

Report date: Thursday. Camp ends: Aug. 22.

Camp site: Team headquarters, Santa Clara.

Practices: Closed to public, except for selected dates/times – Saturday, 9 a.m.; July 27, 9 a.m. and 4 p.m.; July 28, 4 p.m.; July 30, 4 p.m.; Aug. 1, 4 p.m.; Aug. 2, 9 a.m.; Aug. 3, 4 p.m.

Coach: Mike Nolan, fourth season.

Record: 16-32.

Last season: 5-11, third place NFC West.

Key additions: Justin Smith, DE, free agent; Isaac Bruce, WR, FA; Bryant Johnson, WR, FA; Kentwan Balmer, DE, draft; Chilo Rachal, G, draft.

Key losses: Bryant Young, DE, retired.; Larry Allen, G, contract expired; Justin Smiley, G, FA; Kwame Harris, T, FA.

Key preseason dates: Aug. 26, roster cutdown to maximum of 75 players; Aug. 30, roster cutdown to maximum of 53 players; Aug. 31, clubs may establish practice squad of eight players.

Team Web site: www.sf49ers.com

Read Matthew Barrows' blogs at sacbee.com/blogs