INDIANAPOLIS (AP) The Colts keep trying to find that perfect offensive mix.
With Andrew Luck and a deep corps of receivers, they know they could have one of the league's most potent passing games in 2014. The hard part has been giving Luck a solid running game that is still trying to get off the ground.
Three seasons into coach Chuck Pagano's tenure, Indy's most experienced running backs -- Trent Richardson and Ahmad Bradshaw -- have combined for just 53 yards on 23 carries in three preseason games.
''It's going to be a work in progress the whole season,'' Pagano said Monday. ''All we want to do is be better tomorrow than we were today or the next day or the next game.''
During Saturday night's miserable performance against New Orleans, Richardson carried six times for 17 yards, Bradshaw carried three times for two yards and Luck had the best showing among the starters with two carries for 22 yards. The numbers improved dramatically in the second half, thanks in large part to a 43-yard run from Daniel Herron, but there's plenty of room for improvement.
Richardson has continued to be a favorite target for critics, who argue the Colts gave up their first-round pick in May and have yet to see a payoff. Last season, Richardson averaged 2.9 yards per carry after coming over from Cleveland, and the conventional wisdom was that a full offseason in Indy's system would help the No. 3 overall pick in the 2012 draft regain his timing down and find more success.
The result: He's averaging 2.8 yards this preseason.
Bradshaw has been limited throughout much of training camp as he tries to return from neck surgery and ran only three times for two yards against the Saints in his first preseason action.
The third guy in the backfield rotation was expected to be Vick Ballard, who sustained a season-ending torn Achilles' tendon last month. That has opened the door for Herron, who leads the Colts with 18 carries for 104 yards to make the team.
Players and coaches say they understand what's wrong.
''It comes with guys straining a little more to stay on blocks or get on blocks,'' tight end Dwayne Allen said. ''We've been able to go through the film and there are some big plays out there. But it's not the runner, it's the blocking.''
Part of the explanation could be the mix-and-mash lineups the Colts have used because of injuries.
Indy lost starting left guard Donald Thomas before the first preseason game and projected starting center Khaled Holmes hasn't practiced or played since spraining his left ankle on the first possession of the first preseason game. Second-round draft pick Jack Mewhort, who split snaps at center and left guard after Holmes' injury, has been dealing with a sore right knee and seventh-round draft pick Ulrick John is expected to miss substantial time with a lower right leg injury.
Undrafted rookie Jonotthan Harrison, who started the last two games at center, is now hurt, too. He missed Monday's practice with a sprained right thumb.
Though Pagano remains hopeful Holmes will start Sept. 7 season at Denver, the Colts know they can't afford to start making excuses.
''There's a standard for everybody who gets in the game and that's to do well and get better,'' Luck said.
While the numbers don't show it, Luck insists the Colts are progressing and Pagano said he believes the Colts are heading in the right direction. But the real test won't come in Thursday night's preseason finale at Cincinnati, when most of the starters will be on the bench.
Indy will have to wait until the season-opener to see if they've finally found a recipe for the power-running game it wants.
''It's just paying attention to details,'' Allen said. ''We've had some success, but the not the success that catches people's eyes.''
Notes: Colts players and coaches attended a memorial service Sunday for Maveah Alice Hughes, the 3-month-old daughter of defensive tackle Montori Hughes who recently died from a sudden illness. Hughes has missed almost two weeks of practice and did not play Saturday. ... Darius Butler, the Colts' No. 3 cornerback, sat out Monday with an undisclosed ankle injury. Defensive lineman Arthur Jones did practice after leaving Saturday's game with a rib injury. ... Pagano said that Delano Howell, who was battling for the starting job at safety, is still get evaluations on his injured neck.
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