Ryan Tannehill now has plenty of potential pass targets, thanks to a spending spree by the Miami Dolphins.Miami signed tight end Dustin Keller and wideout Brandon Gibson on Friday to complete a much-needed upgrade of the receiving corps. The Dolphins earlier added Mike Wallace, the top pass-catcher in free agency, and re-signed wideout Brian Hartline last week.The moves transform the passing game into a potential strength, with Tannehill the triggerman. He became the first Dolphins rookie to start all 16 games at quarterback last year, and finding more targets for him was the No. 1 offseason priority."We feel that we have added some very good pieces to our passing game," general manager Jeff Ireland said.Keller and Gibson agreed."In today's NFL, you've got to have more than one or two ways to get people the ball," Gibson said. "This is a young and talented group. If we stick together, we could be very good."Keller, who has 17 career touchdown catches, signed a one-year contract as a replacement for Anthony Fasano, the Dolphins' starting tight end the past four years. Fasano signed Tuesday with the Kansas City Chiefs.Keller has 20 catches of at least 25 yards over the past five years, compared with 11 for Fasano, and said he looked forward to working with Tannehill."I've been following him for a while," Keller said. "He does a great job. To have a guy who can work the middle of the field and stretch the field, I think I can really help him out."Keller was slowed by a left ankle injury last year, when he made 28 catches for 317 yards and two scores in eight games."It was pretty frustrating," he said. "This is a fresh start for me. It's an opportunity to go somewhere and re-prove myself."A former New York Jet, Keller said he wanted to join a playoff contender and likes the Dolphins' chances under coach Joe Philbin in 2013."Coach Philbin is putting all the pieces together to win now," Keller said. "This team is in a position to win, and that's what we're going to do."The Dolphins are coming off their fourth consecutive losing season, but they did finish a game ahead of the Jets at 7-9.Gibson spent the past four seasons with the St. Louis Rams, where he made 38 starts. Last year he had 51 receptions for a career-high 691 yards and five touchdowns while starting 13 games.While Wallace and Keller should help to spread the field, Gibson expects to play a complementary role."They're going to do a great job of opening things up," he said. "My role I guess is to be the adjuster, see what happens. I could be inside, outside. I might line up in the backfield. Who knows."Regardless, Gibson said he likes the idea of catching Tannehill's passes."I really think he's going to be one of the better young quarterbacks in the NFL," Gibson said. "He has a big arm and is very intelligent, and that will take him a long way."Gibson and Keller have both thrived against the Dolphins. In nine games against Miami, Keller had 35 catches for 395 yards and four TDs, and those performances made an impression on Miami general manager Jeff Ireland."We have been able to see firsthand what kind of impact he brings to an offense," Ireland said.Gibson made a spectacular one-handed catch in the Rams' loss to Miami last October, a play that came up during his contract negotiations with Philbin and Ireland."They might have mentioned it once or twice," Gibson said. "That's a catch you probably won't see too often. I can't say I've made that catch before. My big thing is just to be consistent."