USC Trojans appear to have the horses for a national-title run

Most of the pieces appear to be in place.

An experienced Heisman Trophy candidate at quarterback. Two of the best receivers in college football. A 1-2 punch at tailback courtesy of Penn State. A schedule that seems perfectly manageable.

So what could go wrong for USC, which opens training camp Monday ranked third in the USA Today preseason coaches’ poll?

Injuries, of course, especially if one befalls senior quarterback Matt Barkley.

USC begins the first of three seasons with only 75 players — 10 fewer than the standard annual limit — so depth could become a major issue.

USC’s defense is vastly improved from two years ago, when fans were all but calling for Monte Kiffin’s job as coordinator. But the line, in the wake of end Devon Kennard’s chest surgery on the eve of training camp, is suddenly an even more inexperienced question mark.

USC won its last two national championships with highflying offenses and dominating, turnover-causing defenses led by its line.

The 2003 team that won the Associated Press title ranked first nationally in rushing defense and second in turnover margin. In 2004, the Trojans won their only Bowl Championship Series title with a team that ranked first in rushing defense and turnover margin, third in scoring defense and sixth in total defense.

Last season, the Trojans ranked 18th in rushing defense, 54th in total defense and 71st in turnover margin.

Here are six questions facing USC as it prepares for its Sept. 1 opener against Hawaii:

Can the Trojans handle the pressure?

NCAA sanctions that included a bowl ban allowed the Trojans to adopt an us-against-the-world mentality for two seasons. With no chance to compete for the BCS title or participate in the postseason, the Trojans played the spoiler (see last year’s Oregon game) and then listened to fans and commentators wonder aloud about how they might have fared against Louisiana State or Alabama.

Now USC opens the season ranked at or near the top of the polls. The Trojans could thrive or wilt under the expectations.

Who replaces Kennard at defensive end?

Kennard is expected to be sidelined for much, if not all, of the season. Redshirt freshman Greg Townsend Jr., junior college transfer Morgan Breslin and fourth-year junior Kevin Greene are among the players competing for a starting role opposite senior Wes Horton.

The Trojans also are thin at defensive tackle, so freshman Leonard Williams will get a long look.

How is Robert Woods’ ankle?

Woods, an All-American receiver, sat out spring practice and did not participate fully in off-season team throwing sessions because his surgically repaired right ankle has not healed as anticipated.

However, the junior is expected to be on the field during training camp and when the season begins. Last season, operating at less than full strength because of several injuries, he caught 111 passes and scored 15 touchdowns.

Is Aundrey Walker the answer at left tackle?

The 6-foot-6 Walker has lost about 75 pounds since arriving last summer from Ohio, and coaches regard him as a future NFL first-round draft pick.

But the sophomore has never played on the left side during a game for the Trojans and he must fill the shoes of Matt Kalil, who did not allow a sack in 2011.

Barkley’s security, and perhaps the Trojans’ season, is riding on his performance.

Does Silas Redd’s arrival ensure a successful rushing attack?

It looks that way.

Redd, a junior, rushed for 1,241 yards last season at Penn State and joins a backfield that includes fifth-year senior Curtis McNeal, who rushed for 1,005 in 2011.

At the very least, it shores up a depth issue that was hanging over the Trojans. And if McNeal or Redd is sidelined, keep an eye out for third-year sophomore D.J. Morgan, who ran track during the spring and is motivated to find a role.

Is Barkley a lock to win the Heisman Trophy?

No, but he has the highest national profile and might be better-positioned to do so than any player in recent years.

Neither Andrew Luck nor Robert Griffin III had receivers like Woods, Marqise Lee or incoming freshman Nelson Agholor. Or a running game featuring two 1,000-yard backs.

If Barkley remains healthy — he missed one game in the 2009 and 2010 seasons — Coach Lane Kiffin will make sure he stays on the Heisman radar statistically.

Leading the Trojans to the BCS title game could be the clincher.

gary.klein@latimes.com

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