GLENDALE, Ariz. -- The Angels continued to pare down their roster Thursday, optioning right-handers Parker Bridwell and Nick Tropeano, infielders Kaleb Cowart and Nolan Fontana and catcher Juan Graterol to Triple-A Salt Lake. They also informed the following non-roster players that they will not make the Major League team, but they will remain in camp: left-handers Ian Krol and John Lamb , right-hander Osmer Morales , infielder David Fletcher and outfielders Eric Young and Rymer Liriano .

The latest round of cuts served as another sign that Shohei Ohtani has seemingly solidified his spot in the Angels' rotation, though manager Mike Scioscia said the club hasn't made a decision yet. With Bridwell, Tropeano, Lamb and Morales ticketed for the Minors, Ohtani is one of six starters remaining in big league camp, along with Garrett Richards , Tyler Skaggs , Matthew Shoemaker , JC Ramirez and Andrew Heaney , who is currently sidelined with left elbow inflammation.

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While the Angels still plan on using a six-man rotation this season, Scioscia said they will carry five starters on their Opening Day roster, as they have an off-day on April 5 that allows them to go without a sixth starter until April 12. Heaney could be ready to pitch by then, with Bridwell and Tropeano as potential fallback options.

"Out of the gate, we're not going to really need that extra starter for a while," Scioscia said following the Angels' 4-3 loss to the Dodgers at Camelback Ranch on Thursday night. "Those guys [Tropeano and Bridwell] are still in the running. We're trying to see where Andrew is. There's a lot of things in question, but it'll give us a little flexibility as we start the season, since we're probably not going to be at a full rotation at that point."

By opening the season with a standard five-man rotation, the Angels will have room to carry an extra reliever or bench player on their roster.

"There's a lot of different things that we could consider," Scioscia said.

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Nine relievers remain in camp, with Richard Parker , Cam Bedrosian , Jim Johnson, Jose Alvarez , Blake Wood and Keynan Middleton likely to earn spots in the bullpen. That leaves three contenders for the final openings: Rule 5 Draft pick Luke Bard , Noe Ramirez and Felix Pena .

Bard, who must be offered back to the Twins if he isn't on the Angels' 25-man roster for the entire 2018 season, has logged a 6.10 ERA over 10 1/3 innings this spring. However, that figure is skewed by a Feb. 28 outing against the Indians, in which he allowed five runs in one-third of an inning.

Ramirez is out of options and has recorded a 4.76 ERA, while walking two and striking out 14, over 11 1/3 innings this spring. He entered Thursday night's game against the Dodgers in the fourth inning with runners on first and second and no outs, then worked out of the jam by striking out John Forsythe and Joc Pederson and coaxing a groundout from Austin Barnes . Ramirez returned to the mound in the fifth and allowed a solo home run to Corey Seager before completing his two-inning outing.

Pena replaced Ramirez in the sixth and gave up a leadoff homer to Cody Bellinger before retiring the next three batters. He has posted a 4.50 ERA, while walking two and striking out 13, over 10 innings this spring.

Backup catcher Rene Rivera and outfielder Chris Young are locks for the Angels' bench, leaving Jefry Marte and Chris Carter as the remaining contenders for reserve infield jobs. Marte is more likely to earn a spot, as he offers more positional flexibility and is out of options. Carter has performed well this spring, batting .306 with three home runs in 20 Cactus League games, but he is currently behind Jose Pujols and Luis Valbuena on the depth chart at first base.

Catcher Carlos Perez is also still in camp, but he is unlikely to make the team and is out of options, so his future with the organization remains unclear.