There are also questions about whether Nick Johnson can fully recover from a broken leg or whether Nook Logan can hit enough to be an everyday center fielder.
But manager Manny Acta doesn't appear to be worried about the offense. He already has an idea of what his lineup will be entering Spring Training. On his first day on the job, Acta announced that second baseman Felipe Lopez would replace Soriano at the leadoff spot. It will help that Lopez set career highs last year in walks, stolen bases and runs scored.
"Hitting leadoff will not be a big transition for me," Lopez said. "I was getting on base hitting second behind Soriano. I'm going to treat it the same -- just get on base like I did last year and score a lot of runs.
"I'm looking to improve, however. I want to cut down on the strikeouts. Even though I walked a lot, I want to put the ball in play a lot more and be aggressive."
With Lopez moving up a notch in the lineup, Acta indicated that Cristian Guzman could bat second in the order. The problem is, Guzman is coming off a tough 2005 season and missed all of 2006 because of shoulder surgery.
"We are going to see if the laser eye surgery that Guzzie had is going to work and if he is back to his days in Minnesota," Acta said. "We will probably give him a shot to be the second hitter."
There are at least four candidates who have a chance to replace Soriano in left field -- Kory Casto, Ryan Church, Alex Escobar and Chris Snelling -- and none of them has played a full season in the big leagues.
Casto began the 2006 season as the starting third baseman for Double-A Harrisburg. Before last July's non-waiver trade deadline, however, assistant general manager Bob Boone told Casto to switch to left field, as the Nationals were planning to call him up had Soriano been traded before the deadline.
In 2005, Casto, the organization's Minor League Player of the Year the past two seasons, hit .290 with 22 home runs and 90 RBIs for Class A Potomac. Last season, he had a .272 average with 20 home runs and 80 RBIs for Harrisburg. He also spent time in the Arizona Fall League, hitting .302 with nine RBIs.
Church had an up-and-down 2006 season, spending half of his time in the Minors. He finished strong, though, winding up at .276 with 10 home runs and 35 RBIs in 196 at-bats.
Acta placed a call to Church in December and gave the young outfielder nothing but positive reinforcement. Church, according to Acta, was happy to hear from his new boss, and he feels that he can have a fresh start with the Nationals in 2007.
"I've always gotten along with Church when I was in Montreal," Acta said. "It's going to be up to him. This is a make-or-break year for him to show the world what he can do, or go in the other direction by becoming a fourth [outfielder]."
No one has ever questioned Escobar's talent with the bat or glove, but he has had problems staying healthy over the past five seasons. Escobar's 2006 season came to an end in late August after he separated his shoulder while diving toward first base.
Escobar is expected to be 100 percent by Spring Training, and Acta said that he was going to give Escobar a chance to win the job in left.
The 25-year-old Snelling, who was acquired from the Mariners in the Jose Vidro trade in December, has some big-league experience. In 59 games and 152 career at-bats, he has hit .237 with five home runs and 12 RBIs, but he comes with caution. Snelling has been injury-prone during his eight years in professional baseball, having undergone 10 operations, seven of which were on his left knee. He first hurt the knee in 2002, tearing his ACL while trying to stop at third base.
Snelling's best season was in 2001, when he hit .336 with seven home runs and 73 RBIs for Class A San Bernardino. He had his worst season in 2006, hitting .216 with five home runs and 39 RBIs for Triple-A Tacoma.
Acta said that his best hitter will always bat third, and that will be Ryan Zimmerman, who led the team in RBIs with 110 and finished as one of the top rookies in baseball last season. Asked if it was too much to expect Zimmerman to have a season like he had in 2006, general manager Jim Bowden said, "History shows us that the second year is a lot more difficult for hitters, but not every hitter. They pitch to you a little bit better after seeing you. It depends on the adjustments you make. Certainly, Ryan has the talent and the ability to continue his success."
The biggest question mark is Johnson, who broke his right leg in a collision with Austin Kearns on Sept. 23. Johnson said a few weeks ago that he was still limping and most likely will not be ready for Spring Training or Opening Day.
Larry Broadway is the front-runner to replace Johnson. Broadway, 26, came back from an injury-filled 2005 season to hit .288 with 15 home runs and 78 RBIs for Triple-A New Orleans in 2006. But if Broadway doesn't hit, the Nationals have non-roster invitee Travis Lee as insurance. Lee is considered an outstanding defensive first baseman, but he's coming off one of his worst seasons. In 114 games with the Devil Rays last year, the 31-year-old Lee hit .224 with 11 home runs and 31 RBIs. Tampa Bay released Lee in early September.
"Nick Johnson is hurt, and Larry Broadway is not hitting in winter ball," Bowden said. "We are short on depth. Lee is a good defensive first baseman, and he's only 31. Does he make this team? I don't know. If Nick is hurt and Broadway doesn't hit and his knee acts up again, then what you are going to do?"
There are also questions about Logan's hitting. Most scouts consider him a Major League hitter from the right side but feel that he has limitations from the left. Logan is a good bunter from the left side, but he has problems hitting offspeed pitches.
Logan insists that there will be improvements in his game from the left side. This offseason, he often talked with hitting coach Mitchell Page and has worked with Sid Hollins, a hitting coach in the Houston area who was recommended to Logan by Devil Rays outfielder Carl Crawford.
"I feel better at this stage than I've been all of my career," Logan said. "There are minor adjustments. It's about staying back and letting the ball travel to me. I've been switch-hitting since I was 21. I've been hitting right-handed all my life. Naturally, I'm going to be better right-handed. I'm a work in progress from the left side."
Bill Ladson is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.