Updated

By taking a moribund rushing attack, adding one elite running back and mixing well for one week -- presto! -- the Indianapolis Colts cooked themselves up a top-shelf ground game.

Perceived as a troubled offense after starting runner Vick Ballard went down with a season-ending injury, Coach Chuck Pagano and Co. have gone old-school en route to a reinvigoration.

The Colts plucked former New York Giants feature back Ahmad Bradshaw off the bench and purloined 1,000-yard rookie Trent Richardson from the Cleveland Browns while providing quarterback Andrew Luck with a reliable non-throwing outlet for scoring points.

Indianapolis went burly and bruising against a similarly equipped San Francisco team in Week 3, and ground down the reigning NFC champions on the way to a possibly season-defining 27-7 victory.

This week, they go to the other end of the spectrum with a visit to Jacksonville at EverBank Field.

Richardson scored on his initial carry while wearing the horseshoe and Bradshaw woke up the echoes with 95 yards and a TD on 19 carries while helping the Colts compile 179 rush yards as a unit. It was the third straight week in triple-digits for Indianapolis, which is fourth in the league with 146.3 per game.

The new weapon has taken the heat off second-year man Luck, whose 164 yards against the Niners were a career low. He passed for more than 4,300 yards as rookie while the Colts posted a shade more than 100 yards per week on the ground. In three games this season, he's passed for less than 200 yards twice -- both in games Indianapolis won.

"That was a definite step in the right direction," said Colts left tackle Anthony Castonzo. "A lot of that has to do with the fact that we just have backs that are fun to block for."

On defense, Indy got to San Francisco QB Colin Kaepernick three times and intercepted him once. The Niners' lone TD came on a 13-yard run by Kendall Hunter and they managed just 254 total yards.

"It was as complete a game as I think we've played since we've been here," Pagano said.

A win for the Colts will give them their best start since going 14-0 in 2009, and it seems within reach -- particularly on the ground -- against a Jacksonville team that's allowed a league-worst 167.7 yards per game through three weeks and was gashed for 156 in a 45-17 loss at Seattle last week.

The Jaguars have lost eight in a row and 15 of 16 while allowing 29.1 points per game.

"It's a pretty clear picture," first-year coach Gus Bradley said. "But I don't want to say that in regards to saying, 'OK, we're three years away.' That's not how we think. We're just trying to get these guys to play at their highest level."

To make matters worse, Jacksonville is also last in the league with just 230.3 yards per game on offense, and it will re-insert season-beginning starter Blaine Gabbert at quarterback after he sliced open his throwing hand in a Week 1 loss to Kansas City. Gabbert was also hurt when he last faced the Colts, sustaining a shoulder injury in a 27-10 loss last November.

Former Miami Dolphin Chad Henne started the last two games in Gabbert's absence and connected with wide receiver Cecil Shorts 16 times for 236 yards. Among the other possible options, tight end Marcedes Lewis (calf) is questionable to make his season debut.

For his part, Shorts remains upbeat about the Jaguars' progress.

"We are a very young team and we are still learning," he said. "We still have a lot of stuff to improve on and we'll hit it hard this week."

Also dogged by physical issues has been workhorse running back Maurice Jones- Drew, who's averaged 153.3 yards against the Colts in his last three matchups, but is compiling only 2.6 yards per carry this season while dealing with a bum ankle.

Indianapolis is 26th in the league against the run, allowing 129.0 yards per game.

WHAT TO WATCH FOR

Given the mediocre numbers he's put up while going 5-20 as a starter over parts of three NFL seasons, Gabbert certainly seems up against it while facing a Colts defense that reined in Kaepernick in last week's 20-point win.

Indianapolis is sixth in the league in scoring defense and 11th in passing yardage.

After the success they had last week against San Francisco, Colts running backs Bradshaw and Richardson must be licking their collective chops at the prospect of facing the Jaguars -- who are last in rushing defense (167.7 yards per week), third from last in average yards per carry (5.2) and fifth from last in opposition rushing attempts (97) through three weeks.

OVERALL ANALYSIS

The Jaguars are home, they have their starting quarterback back in the fold and they're facing a team coming off a huge victory against a spotlight opponent on the West Coast.

All the elements are there to warrant use of the hackneyed "trap game" analysis. All the elements, that is, except the presence of comparable talent on the hosts' side of the field. Instead, expect the Jags to be grounded and pounded -- just as the elite Niners were at Candlestick Park -- on the way to a fourth straight one-sided defeat.

Sports Network predicted outcome: Colts 27, Jaguars 13.