ESPN NFL

Second-year quarterback Christian Ponder has the Minnesota Vikings heading in the right direction and on the verge of matching their win total of last season.

To do so, they'll have to end a three-game losing streak to the Detroit Lions, who are optimistic that quarterback Matthew Stafford will be healthy enough to go Sunday at Ford Field.

Ponder is second in the NFL with a 70.1 completion percentage and fifth in passer rating at 104.9. He went 21 of 35 for 198 yards and two touchdowns in a 24-13 victory over previously undefeated San Francisco last week.

"The more plays I get, the more film I watch, it slows down and I just feel so much more comfortable in what I'm doing," said Ponder, who also ran for a score. "And it helps when the players around you are playing so well."

Adrian Peterson has made a remarkable recovery from a knee injury with 230 rushing yards, and wide receiver Percy Harvin has a league-high 27 receptions and is fourth in kickoff return average at 30.0 yards.

Though the Vikings (2-1) are third in the NFL with four rushing plays of 20-plus yards, they rank 29th with six completions of 20-plus yards. The season debut of speedster Jerome Simpson could help Minnesota start to stretch pass defenses.

Acquired in April, Simpson was suspended the first three games for violating the league's substance-abuse policy.

"We want to utilize his talents as soon as possible," coach Leslie Frazier said. "He's chomping at the bit to get out there and help us but we want to get him integrated right away."

A deep threat could cause plenty of problems for a Lions team that's allowing 31.3 points per game -- sixth highest in the league. Detroit (1-2) surrendered 437 yards and a league-record five scoring plays of 60 or more yards -- two on passes -- in a 44-41 overtime loss to Tennessee last Sunday.

Cornerbacks Chris Houston and Bill Bentley returned last week after missing time with injuries, but it's uncertain when safety Louis Delmas will play after undergoing knee surgery last month. Plus, starting defensive tackle Corey Williams -- a key run-stopper who might have played a big role against Peterson -- had knee surgery this week that rules him out for Sunday.

"It's a big-time loss," defensive tackle Nick Fairley said.

Stafford was replaced by Shaun Hill in the fourth quarter last Sunday after suffering a leg injury while chasing a Tennessee defender on a 72-yard fumble return for a touchdown. However, he appeared healthy enough to play this week during practice, barring a surprising setback.

"I feel better than I did yesterday," Stafford said Thursday. "We'll see how it goes. That's my story, and I'm sticking to it."

Hill went 10 for 13 for 172 yards last week, throwing TD passes to Calvin Johnson and Titus Young in the final 18 seconds of regulation.

Whoever starts under center will face a Vikings team giving up 19.7 points per game, ninth lowest in the league.

Slowing down Johnson, the league leader with 369 receiving yards, will be a priority. However, the Vikings will also have to pay attention to running back Mikel LeShoure.

Making his NFL debut after missing last season with an Achilles' injury and the first two games of 2012 for violating the league's substance abuse policy, LeShoure ran for 100 yards last Sunday, including a one-yard TD.

The Lions' 11 rushing first downs were their most since Nov. 25, 2010.

Detroit totaled two rushing first downs and 92 yards on the ground last season while sweeping this NFC North series for the first time since 1997.

Stafford threw for 605 yards and four TDs in those contests -- two to Johnson -- while Ponder's only appearance came in a 34-28 loss at Ford Field on Dec. 11.

He was replaced by Joe Webb in the third quarter of that game after getting intercepted three times and losing a fumble on the Vikings' first offensive play of the game.

Detroit, which last dropped three straight during a five-game slide Nov. 7-Dec. 5, 2010, has won two in a row at home versus Minnesota after losing seven of eight. The Lions haven't won four in a row in this series since a five-game run Nov. 19, 1961-Oct. 27, 1963.