MIAMI GARDENS, FLA. – Lamar Jacksonnever got cooking Monday night against the Indianapolis Colts, and afterward the Ravens quarterback insisted on one big reason: There was never any heat in the first place.

Six times in a seven-question span at his postgame news conference, the No. 32 overall draft pick referenced warmth: He hadn’t warmed up before he missed his first four passes. He hadn’t stayed warm as he went 7-for-15 for 49 yards and a touchdown. To do better, he needed, among other things, better warmth.

After Saturday night’s 27-10 win over the Miami Dolphins, a second-half showcase of Jackson’s ability that might have dented Robert Griffin III’s own case for the 53-man roster, coach John Harbaugh called it the rookie’s breakout game. Jackson finished 7-for-10 for a team-high 98 passing yards and a touchdown, along with three carries for 39 yards and a touchdown, by far his best stat line of an erratic August.

But it might have been the 20 throws no one was recording that made the Ravens’ 12th straight preseason win possible. With Griffin (9-for-15 for 66 yards) playing the whole first half Saturday, first-year quarterbacks coach James Urban urged Jackson to stay loose. He told Jackson to throw 10 passes right before halftime. Then Urban had him throw another 10 passes before his third-quarter debut.

“That was all Coach Urbs,” Jackson said. “He was on me.”

And did it matter? “Absolutely,” he said. After missing on his first pass, to tight end Mark Andrews, Jackson said he resolved that he would not start as poorly as he had against the Colts. Facing a possible three-and-out on his first possession, he scrambled 13 yards on third-and-13. Then he found wide receiver Breshad Perriman for a short gain. Then running back De’Lance Turner burst through the middle for a 65-yard, game-tying touchdown.

Two drives later, the Ravens were in the end zone once more and ahead for the first time, Jackson again having overcome a drive-starting incompletion to connect on his next three passes. In all, the Ravens scored touchdowns on three of his four drives, and they struck quickly. Jackson’s longest-developing scoring drive took 2:34, and the other two were around two minutes long.

That was by design. The Ravens hurried their huddles up with Jackson under center, if they huddled at all, testing and torturing the Dolphins’ backups with his speed and dual-threat ability.

“We’ve seen it in practice where he’s done some really good things, but we hadn’t really seen it in a game yet,” Harbaugh said. “And today just fell into place for him a little bit. I thought [offensive coordinator] Marty [Mornhinweg] did a really nice job with the play-calling, but he handled himself well. He got to the line of scrimmage, he made calls, he made checks, made adjustments.”

It might prove to be Jackson’s last preseason appearance this year. Harbaugh said that even with the number of Ravens starters who sat out Saturday’s game, including quarterback Joe Flacco, Thursday’s preseason finale against the Washington Redskins would be a showcase for the team’s bubble class.

Jimmy Smith confident in defense: Asked how he would spend the Ravens’ first four regular-season games, Jimmy Smith offered a simple alternative to playing.

“Training,” he said Saturday night. “Every day.”

The Ravens’ solution to replacing their top cornerback, suspended for violating the NFL’s personal-conduct policy, will be far from straightforward. The defense has by now gotten used to playing without Smith for stretches, but it was appreciably worse against the pass last season when he went out with a season-ending Achilles tendon injury.

In his first comments since the NFL announced Tuesday that it had found evidence of Smith’s “pattern of improper conduct” toward a former girlfriend, he declined to comment further on what the league called “threatening and emotionally abusive behaviors.”

But he did not hesitate to voice his belief in the players who must now perform in his absence.

“I have the ultimate confidence in the defense,” he said after the Ravens’ win over the Dolphins. “They did well. They always do well, I feel like. … We’ll be fine.”

Henry has surgery; rookie Elliott hurt: One day after news broke that top Ravens draft pick and tight end Hayden Hurst was lost for three to four weeks with a stress fracture in his foot, coach Harbaugh indicated another key contributor would miss the season opener and a rookie could miss the entire season.

Defensive tackle Willie Henry had surgery on an umbilical hernia, Harbaugh said Saturday after the Ravens’ win Saturday night, and will be out for “a few weeks.” Harbaugh said the hernia was not football-related; the injury might have been pre-existing and “kind of opened up on him a little bit.” Henry is defensive tackle Brandon Williams’ top backup; behind him on the team’s unofficial depth chart is rookie Zach Sieler.

Sixth-round pick DeShon Elliott appears to have fractured his forearm during Saturday’s game, Harbaugh said. Harbaugh said it’s unclear whether the safety’s injury will be season-ending. The former Texas star had his left arm in a sling as he walked back to the locker room in the second half.

Ravens rookie offensive tackle Greg Senat, who started Saturday’s game before leaving midway through the first half, suffered an injury to his foot or toe, Harbaugh said. The team expected to know the severity of the injury Sunday.

“Once we get to the season, I think those guys will be week-to-week,” Harbaugh said of Henry, Hurst and Senat. “That’ll probably be what it is, and we’ll just see where they’re at.”

jshaffer@baltsun.com

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