BY CAROL MARBIN MILLER AND TERE FIGUERAS NEGRETE

The Cuban father at the center of an international custody battle took the witness stand for the first time Thursday, fending off questions that sought to portray him as a hard-hearted Lothario who abandoned the mother of his child halfway through her pregnancy and allowed his daughter to live in primitive conditions.

Rafael Izquierdo, father of the 4-year-old girl at the center of the dispute, grew increasingly frustrated as a former federal prosecutor, now a lead state child-welfare attorney, grilled him about his romantic past as well as allegations that he conspired to fabricate evidence to make himself appear like a caring father.

''It's not like you portray it,'' said Izquierdo, impatiently addressing attorney Jason Dimitris, who is leading the Department of Children & Families' attempt to keep the little girl with her Coral Gables foster family.

''If the story of my life looks to you that way, it's very easy to talk about it. But I lived through it,'' Izquierdo said.

Much of the tension Thursday focused on Izquierdo's romantic history with Elena Perez, the mother of his 4-year-old daughter, as well as allegations of witness tampering, evidence fabrication and overall misconduct that have dogged the eight-day trial since its inception.

Perez lobbed the accusations against Izquierdo and his attorneys, saying they are lying about the origin of photos she purportedly sent to Cuba and letters he says he sent to her in the United States.

The issue of whether the former lovers communicated after Perez left Cuba has been a key point in the trial: DCF maintains Izquierdo showed little interest in the girl's well-being since he gave permission for her to leave the small town of Cabaiguán with her mother in 2005.

Perez left the island with her two children -- the girl and a now-teenage son fathered by another man -- but found herself in dire financial and emotional straits within months of arriving in the United States.

She called 911 during a suicide attempt in December 2005, prompting the state to remove the children from her care.

Perez's two children are now living with Joe and Maria Cubas in Coral Gables. They have formally adopted Perez's 13-year-old son and want to raise the girl as well.

At one particularly testy moment, Dimitris grilled Izquierdo about a letter Izquierdo said he sent to the girl's mother in the spring of 2005.

In the letter, Izquierdo mentions having received photos of the little girl that show her with a new bicycle, toys and other presents.

The letter is a fake, Dimitris charged. The bike and toys were gifts from the foster parents, who did not take custody of the girl until months after the letter was supposedly written.

Dimitris displayed on a large screen the photograph, which shows the girl smiling atop a gleaming pink Strawberry Shortcake two-wheel bike with training wheels.

''Mr. Izquierdo, isn't it true that the picture you describe in this letter comes from a Christmas photo that was taken of [the girl] while she was in Miami on a bicycle that Mr. Cubas gave her?'' Dimitris demanded, his voice rising. ``Which makes the entire letter a fraud?''

''Please repeat the question. I did not understand the question,'' Izquierdo answered, as attorneys for DCF and the Guardian-ad-Litem program chuckled.

''You have known for days that the bicycle issue destroys your credibility, and yet you don't have an answer to that question today,'' Dimitris persisted.

Izquierdo admitted he did not write another letter called into question, saying his sister wrote it for him and signed his name. He said there was no sinister intent: Cubans often rely on visitors to the island to take letters and packages to the states; his sister simply wrote the letter for him when she chanced upon someone willing to mail it to Perez stateside.

Izquierdo, who relied on a Spanish-language translator during his testimony, accused Dimitris several times of trying to trick him with wordplay.

Izquierdo also complained that DCF was trying to distort his relationship with Perez, whom he met at her job at a pharmacy in Cabaiguán.

Dimitris, who prosecuted white-collar criminals during much of his eight-year career, questioned Izquierdo on the minute details of his relationship with both Perez and Yanara Alvarez, the mother of his 7-year-old daughter.

Izquierdo testified that Alvarez became pregnant with their child when she was 17 and moved out of his house with the infant within eight months. He was 24 at the time.

His relationship with Perez began shortly thereafter, and although the couple never lived together, Izquierdo testified that he considered himself ''married'' to her. Izquierdo also testified that he broke up with Perez ''in the middle'' of her pregnancy and later reconciled with Alvarez.

He conceded he never asked Perez to live at his home in Cuba, an issue Dimitris homed in on, saying Izquierdo lived in relative comfort at his house, which he shares with his parents, while Perez and their daughter lived without an indoor bathroom or a refrigerator, and no running water except for a faucet outside the house.

Izquierdo said he considered the outdoor toilet as part of Perez's home, a parsing of words that irritated Circuit Judge Jeri B. Cohen.

''I'm starting to get a little annoyed,'' the judge told Izquierdo after he and Dimitris quibbled over the plumbing details. ``A grown man knows what we are talking about. You don't need to be a rocket scientist. You don't need a degree from Harvard.''

After Thursday's session ended, Ira Kurzban, an attorney for Izquierdo, said the conspiracy allegations and his client's track record as a boyfriend are irrelevant.

''It has nothing to do with the case,'' he said. ''The issue is whether he abandoned or neglected'' his daughter.