Louis Murphy went into the Buccaneers preseason opener against the Vikings as something of an invisible man in the race for the third wide receiver job. It was on odd role for Murphy. After all, he owned that job last year, playing it so well the Bucs signed him to a three-year contract extension before the season was even over. But in his quest to keep that job this summer, Murphy was quickly eclipsed by the stellar play early in training camp of rookie challengers Kenny Bell and Rannell Hall. Suffice to say, Murphy is no longer playing in anyone’s shadow. Despite getting in only a few days of training camp work — the result of an ankle injury suffered just two weeks before camp started — Murphy made himself conspicuous when it mattered most. In an otherwise rugged outing for the Bucs’ pass catchers, Murphy proved to be rookie quarterback Jameis Winston’s most reliable target in catching all four of the balls thrown his way in a 26-16 loss. “Experience pays,’’ the seven-year veteran said with a wry smile. Murphy made a 17-yard reception to the Vikings 14-yard line to help set up the Bucs’ first score, a 32-yard Patrick Murray field goal. He made three more catches for 37 yards to set up Tampa Bay’s first touchdown. “We’ve gotten consistent play like that from Louis throughout,’’ Bucs coach Lovie Smith said, referring back to last season. “He’s been a valuable guy for us, a guy that we really could depend on.’’ The Bucs reached that conclusion late last season, signing then-injured Murphy to a three-year, $4.66-million contract extension two days before the season ended. It was Murphy’s professional approach and reliable play — he caught 31 passes for 380 yards and two touchdowns — the Bucs found most valuable.