Massive injuries once again hit the NFL in Week 14.

Fantasy football owners cringed as they watched players such as Adrian Peterson, Rob Gronkowski and Wes Welker go out with significant injuries. As fantasy owners enter the semifinals of the playoffs, those blows could have serious implications.

Responding by making the right moves this week could help keep your season afloat, but you're going to have to act fast.

Minnesota's Toby Gerhart will be a hot commodity this week. Peterson's replacement for the Vikings is always a nice handcuff player, but he is available in more than 90 percent of fantasy leagues. Although Adrian Peterson hoped to play this upcoming Sunday against Philadelphia, his status doesn't look probable. But even Gerhart's status is a bit iffy after he tweaked a hamstring on a 41-yard touchdown run late in Sunday's wild finish in Baltimore. Gerhart is a must-add for Peterson owners, but even his status will have to be monitored throughout the week.

The best possible replacement for Gronkowski, the talented but oft-injured New England tight end, is Baltimore's Dennis Pitta. I have talked about adding Pitta in recent weeks, and he was a factor in Baltimore's win Sunday as he caught six balls for 48 yards and a touchdown, though he played less than half of the team's offensive snaps. Baltimore will continue to ease Pitta back into action after he missed the first 13 weeks of the season with a dislocated hip, but quarterback Joe Flacco is sure to target the big tight end in the red zone. The two have hooked up for eight touchdowns in their last 17 games together.

After Welker went down in Denver with his second concussion in a month, the Broncos utilized a lot of two tight end sets. Welker's absence this Thursday night against San Diego is highly likely. That may benefit guys who are already must-starts, such as Demaryius Thomas, Eric Decker and Julius Thomas, but tight end Jacob Tamme also figures to see an increased role if the Broncos continue to line up with two tight ends. Tamme was capable when Julius Thomas was injured for two games, and he will be a nice safety valve for quarterback Peyton Manning.

Jacksonville running back Maurice Jones-Drew has been disappointing this year, and he also stretched a hamstring a little too far in his final carry of last Thursday's win against Houston. He hopes to play this weekend against the Buffalo Bills, but Jordan Todman is likely to get the carries if Jones-Drew can't go. If Jones-Drew doesn't practice Friday, consider Todman as safe bet, especially in deep leagues.

One more deep-league find is Indianapolis Colts rookie wide receiver Da'Rick Rogers. Rogers finally took over snaps from Darrius Heyward-Bey last weekend in Cincinnati. Rogers has emerged as the second best receiver behind T.Y. Hilton in Indy. With a Colts defense that has been burned lately, Andrew Luck and the Colts are going to have to keep throwing to win games down the stretch. Rogers is available in nearly every league, and he is an intriguing flex play against a struggling Houston Texans defense this week.

Sorry to anyone who took my advice on starting the Oakland Raiders defense last week against the New York Jets. What a dud that pick turned out to be as the Raiders finished with negative points.

That is all for this week. Feel free to send any lineup questions to my email or Twitter as you prepare for your playoff matchup.

John Livingston covers sports for The Daily Times and is a member of the Fantasy Sports Writers Association. He can be reached at; 505-564-4648. Follow him on Twitter @jlivi2.