The world number eight, a US Open finalist last September, has a bye to the second round where he will face either the weekend Barcelona runner-up Stefanos Tsitsipas or Spain’s Pablo Andujar.
South African Anderson last competed a month ago in Miami, losing a quarter-finals to Pablo Carreno Busta.
“I’m looking forward to the week, my first on clay this season,” Anderson said. “I’ve had time to prepare.
“I took some time off after Miami, I had some small aches and pains to deal with. But my body is feeling fine now and I have high expectations.
“I’ve never won a title on clay – that would be a top goal for me.”
Anderson, a 2017 semi-finalist here, is coming to Portugal in a much better state than a year ago, when he was unseeded, ranked 66th in the world and returning from injury.
After beating 2015 champion Richard Gasquet in the quarter-finals, he fell in the next round to Gilles Muller.
“Last year I was returning, it was a turnaround week for me,” Anderson said. “It was my first semi-final in some time.
“Now, a year later, I feel great, I’ve come quite a long way since then and improved my ranking.”
The South African said that he continues to gain confidence after his US Open final, which he lost to Rafael Nadal.
“Memories and experience from New York are a nice feeling, something you dream about.
“I’ve got the confidence that I’m able to perform in the Grand Slams. But each week is a different experience.
“It doesn’t matter what happened in the past, it’s who can play better on the day. Making the final was valuable, but you still have to bring your best tennis.”
With qualifying round wrapping up on Monday after weekend rain, Portugal’s wild card Pedro Sousa lifted local hopes with his 6-3, 4-6, 7-6 (7/4) victory over Frenchman Gilles Simon to reach the second round.