An offseason dominated by quarterbacks will have no letup in the draft.

With a pool of five legitimate first-round prospects – Sam Darnold, Josh Rosen, Josh Allen, Baker Mayfield and Lamar Jackson in some order – projections could hold true that four of the first five picks on April 26 could be quarterbacks.

"This is a very good quarterback draft class," new Cleveland Browns GM John Dorsey, who is expected to take Darnold with the first pick, said in an understatement at the Combine earlier this year.

Teams already have splurged in the trade market and free agency to fill quarterback needs, or traded up to improve their position to draft one.

The Detroit Lions are set at quarterback with Matthew Stafford entrenched as the franchise leader. They have a passing interest in the quarterback draft derby—but only for how it will leave players available at positions of need.

Here is a look at where the Lions stand at quarterback going into the draft, the top five prospects and others available, and the spotlight on Rosen – whose change of sports ultimately made him a top prospect.

Lions' QB depth chart: Matthew Stafford starter; Matt Cassel and Jake Rudock backups.

QB draft priority: Backup only possibility.

Free-agent additions: Cassel was signed Monday.

Matt and Matt – Century Club. Stafford and Cassel both have played more than 100 games. Stafford has played 125 regular-season games, all starts for the Lions. Cassel has played 106 for six teams, with 81 starts.

GM Bob Quinn's QB draft record: He followed up his pre-draft comment in 2016 about drafting young QBs for development by using sixth-round picks on Rudock in 2016 and Brad Kaaya in 2017.

Lions QB draft breakdown: Every quarterback drafted ahead of the Lions leaves one more player left at a position where the Lions could be looking for help. Last year, three quarterbacks were off the board before the Lions took linebacker Jarrad Davis with the 21st pick.

This year, at least four quarterbacks should be gone before the Lions pick, and it could be five – or even six – depending on trades and how highly teams value Lamar Jackson of Louisville or one of the other prospects not generally regarded to be in the Top 5.

Rating the top 5: 1. Sam Darnold, Southern Cal:He's likely to go first overall to Cleveland, despite questions about turnovers and physical dimensions that are less than ideal. Big enough at 6-3.3 and 221 pounds, but arm length (31 inches) and hand size (9.3 inches) are on the small side.

Bio/stats line: A two-year starter after a 2015 red-shirt season, Darnold threw 31 TD passes against nine interceptions in 2016 but regressed to a 26-13 ratio in 2017. Darnold is big enough, with a delivery quick enough to warrant being drafted first overall. 2. Josh Rosen, UCLA:Good size for the position (6-4, 226). Not exactly a speed burner but has a quick release and has been accurate. He might be the QB prospect most ready to play as a rookie.

Bio/stats line: A three-year player for the Bruins (2015-17), Rosen had 59 TD passes against 26 interceptions. He missed half the 2016 season with a shoulder injury. A concussion forced him to miss the second half of the final regular-season game of 2017 plus the Cactus Bowl. 3. Josh Allen, Wyoming:Size (6-5, 237) and raw athletic ability (4.75 time in the 40) have drawn comparisons to Eagles QB Carson Wentz, drafted second overall in 2016 and an MVP candidate in 2017 before an injury ended his season. 

Bio/stats line: Allen transferred to Wyoming in 2015 after a year at junior college. His 2015 season ended after two games, with one start, because of a broken collarbone. His stats in 2016-17 are not as impressive as his physical ability. He had completion rates of 56.0 and 56.3 percent for those two seasons, with 44 TD passes and 21 picks. He'll be drafted high on potential, not college production.

4. Baker Mayfield, Oklahoma: There are no questions about college production or play-making ability for the 2017 Heisman Trophy winner, but his size (6-1), playing out of the shotgun in a spread offense and maturity are question marks.

Bio/stats line: Mayfield left Texas Tech after one year (2013), with eight games and five starts and enrolled at Oklahoma. In 39 games and 38 starts, he threw 117 TD passes against 20 picks for the Sooners. Mayfield did not have his best game in a 54-48 loss to Georgia in the Rose Bowl that kept the Sooners from playing Alabama for the national championship.

5. Lamar Jackson, Louisville: An intriguing prospect with some question marks – accuracy and a slight build – but with no questions about his production and playmaking in three seasons at Louisville.

Bio/stats line: After eight starts as a true freshman in 2015, he established himself as the front runner for the 2016 Heisman Trophy by accounting for eight TDs – six passing, two rushing – in the Cardinals' opening game win over UNC-Charlotte. He finished the season with 30 TD passes, 21 rushing TDs and won the Heisman. For his career Jackson had 71 TD passes and 51 rushing TDs, but his highest regular-season completion rate was 59.1 percent in 2017.

Others: Kyle Lauletta, Richmond; Mason Rudolph, Oklahoma State; Mike White, Western Kentucky; Luke Falk, Washington State; Kurt Benkert, Virginia; Nic Shimonek, Texas Tech.; Riley Ferguson, Memphis; Chase Litton, Marshall; J.T. Barrett, Ohio State; Brogan Roback, Eastern Michigan; Logan Woodside, Toledo.

Spotlight -- net gain: Josh Rosen was a highly rated junior tennis player long before he changed paths in sports that would eventually make him one of the top quarterback prospects in this year's draft.

Rosen was a top 10 junior tennis player, but he gave up the sport for football when he got to high school. He preferred the camaraderie of team competition to the isolation of one-on-one in tennis.

"Tennis is pretty lonely," Rosen told reporters when asked about the switch at the NFL Combine this year. "It's an individual sport. All of your friends are your enemies at the same time. It's a really weird relationship.

"I enjoyed the team aspect of football. You get a chance to play alongside your brothers each and every week. That's ultimately what drew me to football over tennis."