Lions coach Jim Schwartz defended his run-heavy game plan for Sunday night's loss to the 49ers. (US Presswire)

After a Lions offense that led the league in passing yards in Week 1 ran the ball on 10 of its first 14, first-down plays against the 49ers on Sunday, seasoned observers of coach Jim Schwartz’s team were left asking the question made famous by the title characters of the movie "Butch Cassidy and the Sundance Kid."

“Who are those guys?”

Lions’ coach Jim Schwartz defended a game plan Monday that saw offensive coordinator Scott Linehan use power rushing plays instead of the short pass routes that were a staple of the team’s Week 1 win over the Rams.  

“San Francisco took an approach that they were going to try to limit the passing game,” Schwartz said. “We need to be able to rush for better than [3.2 yards] a carry.”

Schwartz downplayed suggestions that the increase in rushing plays -- Detroit rushed the ball on 44 percent of its offensive plays Sunday compared to just 27 percent of its Week 1 snaps -- was partly to blame for the Lions' 27-19 loss at Candlestick Park. He said the key to making the run game a viable part of the Lions’ offense is ensuring that the backfield is efficient regardless of the number of rushing plays Detroit calls.

“[In Week 1 we] ran the ball efficiently,” he said. “We didn’t run it a whole lot of times, but we ran it efficiently -- 4.6 (yards per carry), something like that. [Sunday] we ran the ball more, but it wasn’t as efficient. There are a lot of things we can do better.”

Lions fans that are used to their team’s quick-strike passing attack serving as the linchpin of the offense need not worry about a seismic shift away from a healthy diet of targets for Calvin Johnson, Brandon Pettigrew and the rest of the receiving corps. Schwartz’ commitment to a more balanced offense stems from the understanding that a successful run game will create better matchups for QB Matthew Stafford to exploit.

“Not every game are you going to be able to throw for a bunch of yards,” he said. “There’s going to be different ways each game plays out.”

The Lions’ rushing game should receive a major personnel boost this week when RB Mikel Leshoure returns from a two-game suspension. Leshoure looked impressive in Detroit’s last two preseason games, albeit in an exhibition format against lesser talent. His work ethic has impressed Lions’ coaches during his suspension, and Schwartz says the team is looking forward to having the 2011 second-round pick back on the field.

“We’ve been waiting to see him for a long time,” Schwartz said. “We drafted him in the second round. We had high expectations for him. He was showing us all the things we needed before his rookie year when he [ruptured his Achilles and missed his rookie season].”

If Leshoure makes his regular-season debut Sunday, he’ll do so against a Titans defense that could be an ideal opponent to bolster his confidence. Tennessee allowed an average of 155 rushing yards in its first two games, ranking it 30th in the league in rushing defense.

The Lions will need to cut a player from the roster before Leshoure can be reinstated to the active roster. The team has a 48-hour window from the time a player’s suspension ends to announce a roster move that facilitates their return.

Injury to Drayton Florence deals another blow to secondary: Lions CB Drayton Florence injured his right forearm during Sunday’s game. Jim Schwarz admitted that the injury could be long-term. “[Florence] got some preliminary (X-rays done) at [Candlestick Park],” Schwartz said. “He’s going to have some more stuff. It doesn’t look real good, but we’ll see.”

Florence’s injury leaves Detroit with just three healthy corners. CB Chris Houston (ankle) was a limited participant in practice last week, and he worked out before Sunday’s game. Schwartz wouldn’t offer a timetable for his return to game action. Schwartz also wouldn’t offer a definite prognosis for the return of S Louis Delmas, who hasn’t practiced since he underwent knee surgery during training camp.

“I think [Delmas] is trending upward,” he said, “How quickly and whether he’ll be back [in Week 3], only this week will be able to tell us.”

Follow Lions reporter John Kreger on Twitter at @CBSLions and @JohnKreger.